On Tue, Nov 17, 2015 at 7:29 PM, Masahiko Sawada <sawada.m...@gmail.com> wrote:
>
>
> On Tue, Nov 17, 2015 at 10:45 AM, Robert Haas <robertmh...@gmail.com> wrote:
>> On Sun, Nov 15, 2015 at 1:47 AM, Amit Kapila <amit.kapil...@gmail.com>
>> wrote:
>>> On Sat, Nov 14, 2015 at 1:19 AM, Andres Freund <and...@anarazel.de>
>>> wrote:
>>>> On 2015-10-31 11:02:12 +0530, Amit Kapila wrote:
>>>> > On Thu, Oct 8, 2015 at 11:05 PM, Simon Riggs <si...@2ndquadrant.com>
>>>> > wrote:
>>>> > >
>>>> > > On 1 October 2015 at 23:30, Josh Berkus <j...@agliodbs.com> wrote:
>>>> > >>
>>>> > >> On 10/01/2015 07:43 AM, Robert Haas wrote:
>>>> > >> > On Thu, Oct 1, 2015 at 9:44 AM, Fujii Masao
>>>> > >> > <masao.fu...@gmail.com>
>>>> > wrote:
>>>> > >> >> I wonder how much it's worth renaming only the file extension
>>>> > >> >> while
>>>> > >> >> there are many places where "visibility map" and "vm" are used,
>>>> > >> >> for example, log messages, function names, variables, etc.
>>>> > >> >
>>>> > >> > I'd be inclined to keep calling it the visibility map (vm) even
>>>> > >> > if
>>>> > >> > it
>>>> > >> > also contains freeze information.
>>>> > >> >
>>>> >
>>>> > What is your main worry about changing the name of this map, is it
>>>> > about more code churn or is it about that we might introduce new
>>>> > issues
>>>> > or is it about that people are already accustomed to call this map as
>>>> > visibility map?
>>>>
>>>> Several:
>>>> * Visibility map is rather descriptive, none of the replacement terms
>>>> imo come close. Few people will know what a 'freeze' map is.
>>>> * It increases the size of the patch considerably
>>>> * It forces tooling that knows about the layout of the database
>>>> directory to change their tools
>>>>
>>>
>>> All these points are legitimate.
>>>
>>>> On the benfit side the only argument I've heard so far is that it allows
>>>> to disambiguate the format. But, uh, a look at the major version does
>>>> that just as well, for far less trouble.
>>>>
>>>> > It seems to me quite logical for understanding purpose as well. Any
>>>> > new
>>>> > person who wants to work in this area or is looking into it will
>>>> > always
>>>> > wonder why this map is named as visibility map even though it contains
>>>> > information about visibility of page as well as frozen state of page.
>>>>
>>>> Being frozen is about visibility as well.
>>>>
>>>
>>> OTOH being visible doesn't mean page is frozen. I understand that frozen
>>> is
>>> related to visibility, but still it is a separate state of page and used
>>> for
>>> different
>>> purpose. I think this is a subjective point and we could go either way,
>>> it
>>> is
>>> just a matter in which way more people are comfortable.
>>
>> I'm stickin' with what I said before, and what I think Andres is
>> saying too: renaming the map is a horrible idea. It produces lots of
>> code churn for no real benefit. We usually avoid such changes, and I
>> think we should do so here, too.
>
> I understood.
> I'm going to turn the patch back to visibility map, and just add the logic
> of enhancement of VACUUM FREEZE.
Attached latest v24 patch.
I've changed patch so that just adding frozen bit into visibility map.
So the size of patch is almost half of previous one.
Please review it.
Regards,
--
Masahiko Sawada
diff --git a/contrib/pgstattuple/pgstatapprox.c b/contrib/pgstattuple/pgstatapprox.c
index 22c5f7a..e8ebfe9 100644
--- a/contrib/pgstattuple/pgstatapprox.c
+++ b/contrib/pgstattuple/pgstatapprox.c
@@ -87,7 +87,7 @@ statapprox_heap(Relation rel, output_type *stat)
* If the page has only visible tuples, then we can find out the free
* space from the FSM and move on.
*/
- if (visibilitymap_test(rel, blkno, &vmbuffer))
+ if (VM_ALL_VISIBLE(rel, blkno, &vmbuffer))
{
freespace = GetRecordedFreeSpace(rel, blkno);
stat->tuple_len += BLCKSZ - freespace;
diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index 6e14851..c75a166 100644
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -5905,7 +5905,7 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv;
</term>
<listitem>
<para>
- <command>VACUUM</> performs a whole-table scan if the table's
+ <command>VACUUM</> performs an eager freezing if the table's
<structname>pg_class</>.<structfield>relfrozenxid</> field has reached
the age specified by this setting. The default is 150 million
transactions. Although users can set this value anywhere from zero to
@@ -5949,7 +5949,7 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv;
</term>
<listitem>
<para>
- <command>VACUUM</> performs a whole-table scan if the table's
+ <command>VACUUM</> performs an eager freezing if the table's
<structname>pg_class</>.<structfield>relminmxid</> field has reached
the age specified by this setting. The default is 150 million multixacts.
Although users can set this value anywhere from zero to two billions,
diff --git a/doc/src/sgml/maintenance.sgml b/doc/src/sgml/maintenance.sgml
index 5204b34..5a43c28 100644
--- a/doc/src/sgml/maintenance.sgml
+++ b/doc/src/sgml/maintenance.sgml
@@ -352,9 +352,9 @@
Vacuum maintains a <link linkend="storage-vm">visibility map</> for each
table to keep track of which pages contain only tuples that are known to be
visible to all active transactions (and all future transactions, until the
- page is again modified). This has two purposes. First, vacuum
- itself can skip such pages on the next run, since there is nothing to
- clean up.
+ page is again modified), and pages contain only frozen tuples.
+ This has two purposes. First, vacuum itself can skip such pages
+ on the next run, since there is nothing to clean up.
</para>
<para>
@@ -438,28 +438,25 @@
</para>
<para>
- <command>VACUUM</> normally skips pages that don't have any dead row
- versions, but those pages might still have row versions with old XID
- values. To ensure all old row versions have been frozen, a
- scan of the whole table is needed.
+ <command>VACUUM</> skips pages that don't have any dead row
+ versions, and pages that have only frozen rows. To ensure all old
+ row versions have been frozen, a scan of all unfrozen pages is needed.
<xref linkend="guc-vacuum-freeze-table-age"> controls when
- <command>VACUUM</> does that: a whole table sweep is forced if
- the table hasn't been fully scanned for <varname>vacuum_freeze_table_age</>
- minus <varname>vacuum_freeze_min_age</> transactions. Setting it to 0
- forces <command>VACUUM</> to always scan all pages, effectively ignoring
- the visibility map.
+ <command>VACUUM</> does that: a whole-table freezing is forced if
+ the table hasn't been ensured all row versions are frozen for
+ <varname>vacuum_freeze_table_age</> minus <varname>vacuum_freeze_min_age</>
+ transcations.
</para>
<para>
The maximum time that a table can go unvacuumed is two billion
transactions minus the <varname>vacuum_freeze_min_age</> value at
- the time <command>VACUUM</> last scanned the whole table. If it were to go
- unvacuumed for longer than
- that, data loss could result. To ensure that this does not happen,
- autovacuum is invoked on any table that might contain unfrozen rows with
- XIDs older than the age specified by the configuration parameter <xref
- linkend="guc-autovacuum-freeze-max-age">. (This will happen even if
- autovacuum is disabled.)
+ the time <command>VACUUM</> last scanned unfrozen pages. If it were to go
+ unvacuumed for longer than that, data loss could result. To ensure
+ that this does not happen, autovacuum is invoked on any table that might
+ contain unfrozen rows with XIDs older than the age specified by the
+ configuration parameter <xref linkend="guc-autovacuum-freeze-max-age">.
+ (This will happen even if autovacuum is disabled.)
</para>
<para>
@@ -490,8 +487,7 @@
a regularly scheduled <command>VACUUM</> or an autovacuum triggered by
normal delete and update activity is run in that window. Setting it too
close could lead to anti-wraparound autovacuums, even though the table
- was recently vacuumed to reclaim space, whereas lower values lead to more
- frequent whole-table scans.
+ was recently vacuumed to reclaim space.
</para>
<para>
@@ -527,7 +523,7 @@
<structname>pg_database</>. In particular,
the <structfield>relfrozenxid</> column of a table's
<structname>pg_class</> row contains the freeze cutoff XID that was used
- by the last whole-table <command>VACUUM</> for that table. All rows
+ by the last whole-table freezing for that table. All rows
inserted by transactions with XIDs older than this cutoff XID are
guaranteed to have been frozen. Similarly,
the <structfield>datfrozenxid</> column of a database's
@@ -555,17 +551,19 @@ SELECT datname, age(datfrozenxid) FROM pg_database;
<command>VACUUM</> normally
only scans pages that have been modified since the last vacuum, but
<structfield>relfrozenxid</> can only be advanced when the whole table is
- scanned. The whole table is scanned when <structfield>relfrozenxid</> is
- more than <varname>vacuum_freeze_table_age</> transactions old, when
- <command>VACUUM</>'s <literal>FREEZE</> option is used, or when all pages
- happen to
- require vacuuming to remove dead row versions. When <command>VACUUM</>
- scans the whole table, after it's finished <literal>age(relfrozenxid)</>
- should be a little more than the <varname>vacuum_freeze_min_age</> setting
- that was used (more by the number of transactions started since the
- <command>VACUUM</> started). If no whole-table-scanning <command>VACUUM</>
- is issued on the table until <varname>autovacuum_freeze_max_age</> is
- reached, an autovacuum will soon be forced for the table.
+ frozen. The whole-table freezing is occuerred only when all pages happen to
+ require freezing to freeze rows. In other cases such as where
+ <structfield>relfrozenxid</> is more than <varname>vacuum_freeze_table_age</>
+ transcations old, where <command>VACUUM</>'s <literal>FREEZE</> option is used,
+ <command>VACUUM</> can skip the pages that all tuples on the page itself are
+ marked as frozen.
+ When all pages of table are eventually marked as frozen by <command>VACUUM</>,
+ after it's finished <literal>age(relfrozenxid)</> should be a little more
+ than the <varname>vacuum_freeze_min_age</> setting that was used (more by
+ the number of transcations started since the <command>VACUUM</> started).
+ If the advancing of <structfield>relfrozenxid</> is not happend until
+ <varname>autovacuum_freeze_max_age</> is reached, an autovacuum will soon
+ be forced for the table.
</para>
<para>
@@ -642,28 +640,28 @@ HINT: Stop the postmaster and vacuum that database in single-user mode.
<structname>pg_class</>.<structfield>relminmxid</> stores the oldest
possible multixact ID still appearing in any tuple of that table.
If this value is older than
- <xref linkend="guc-vacuum-multixact-freeze-table-age">, a whole-table
+ <xref linkend="guc-vacuum-multixact-freeze-table-age">, a table
scan is forced. <function>mxid_age()</> can be used on
<structname>pg_class</>.<structfield>relminmxid</> to find its age.
</para>
<para>
- Whole-table <command>VACUUM</> scans, regardless of
- what causes them, enable advancing the value for that table.
+ When <command>VACUUM</> scans all unfrozen pages, regardless of what causes
+ them, enable advancing the value for that table.
Eventually, as all tables in all databases are scanned and their
oldest multixact values are advanced, on-disk storage for older
multixacts can be removed.
</para>
<para>
- As a safety device, a whole-table vacuum scan will occur for any table
- whose multixact-age is greater than
- <xref linkend="guc-autovacuum-multixact-freeze-max-age">. Whole-table
+ As a safety device, a vacuum scan will occur for any table whose
+ multixact-age is greater than
+ <xref linkend="guc-autovacuum-multixact-freeze-max-age">. A
vacuum scans will also occur progressively for all tables, starting with
those that have the oldest multixact-age, if the amount of used member
storage space exceeds the amount 50% of the addressable storage space.
- Both of these kinds of whole-table scans will occur even if autovacuum is
- nominally disabled.
+ Both of these kinds of scans will occur even if autovacuum is nominally
+ disabled.
</para>
</sect3>
</sect2>
@@ -743,8 +741,8 @@ vacuum threshold = vacuum base threshold + vacuum scale factor * number of tuple
<command>UPDATE</command> and <command>DELETE</command> operation. (It
is only semi-accurate because some information might be lost under heavy
load.) If the <structfield>relfrozenxid</> value of the table is more
- than <varname>vacuum_freeze_table_age</> transactions old, the whole
- table is scanned to freeze old tuples and advance
+ than <varname>vacuum_freeze_table_age</> transactions old, the table is
+ scanned to freeze old tuples and advance
<structfield>relfrozenxid</>, otherwise only pages that have been modified
since the last vacuum are scanned.
</para>
diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml
index e64b7ef..1908a4d 100644
--- a/doc/src/sgml/monitoring.sgml
+++ b/doc/src/sgml/monitoring.sgml
@@ -1332,6 +1332,11 @@ postgres 27093 0.0 0.0 30096 2752 ? Ss 11:34 0:00 postgres: ser
<entry>Estimated number of rows modified since this table was last analyzed</entry>
</row>
<row>
+ <entry><structfield>n_frozen_page</></entry>
+ <entry><type>integer</></entry>
+ <entry>Number of frozen pages</entry>
+ </row>
+ <row>
<entry><structfield>last_vacuum</></entry>
<entry><type>timestamp with time zone</></entry>
<entry>Last time at which this table was manually vacuumed
diff --git a/doc/src/sgml/ref/pgupgrade.sgml b/doc/src/sgml/ref/pgupgrade.sgml
index eb113c2..d613bb7 100644
--- a/doc/src/sgml/ref/pgupgrade.sgml
+++ b/doc/src/sgml/ref/pgupgrade.sgml
@@ -657,6 +657,12 @@ psql --username postgres --file script.sql postgres
</para>
<para>
+ Since the format of visibility map has been changed in version 9.6,
+ <application>pg_upgrade</> does not support upgrading of database
+ from 9.5 or before to 9.6 or later with link mode (-k).
+ </para>
+
+ <para>
All failure, rebuild, and reindex cases will be reported by
<application>pg_upgrade</> if they affect your installation;
post-upgrade scripts to rebuild tables and indexes will be
diff --git a/doc/src/sgml/storage.sgml b/doc/src/sgml/storage.sgml
index 164d08c..5dc8b04 100644
--- a/doc/src/sgml/storage.sgml
+++ b/doc/src/sgml/storage.sgml
@@ -623,18 +623,20 @@ can be used to examine the information stored in free space maps.
<para>
Each heap relation has a Visibility Map
(VM) to keep track of which pages contain only tuples that are known to be
-visible to all active transactions. It's stored
-alongside the main relation data in a separate relation fork, named after the
-filenode number of the relation, plus a <literal>_vm</> suffix. For example,
-if the filenode of a relation is 12345, the VM is stored in a file called
-<filename>12345_vm</>, in the same directory as the main relation file.
+visible to all active transactions, and pages contain only unfrozen tuples.
+It's stored alongside the main relation data in a separate relation fork,
+named after the filenode number of the relation, plus a <literal>_vm</> suffix.
+For example, if the filenode of a relation is 12345, the VM is stored in a file
+called <filename>12345_vm</>, in the same directory as the main relation file.
Note that indexes do not have VMs.
</para>
<para>
-The visibility map simply stores one bit per heap page. A set bit means
-that all tuples on the page are known to be visible to all transactions.
-This means that the page does not contain any tuples that need to be vacuumed.
+The visibility map stores two bits per heap page: all-visible, all-frozen.
+A set all-visible bit means that all tuples on the page are known to be visible
+to all transactions. A set all-frozen bit means that all tuples on the page are
+completely marked as frozen. This means that the page does not contain any tuples
+that need to be vacuumed, even if a scan of whole table is required.
This information can also be used by <firstterm>index-only scans</> to answer
queries using only the index tuple.
</para>
diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c
index 35a2b05..60eb41f 100644
--- a/src/backend/access/heap/heapam.c
+++ b/src/backend/access/heap/heapam.c
@@ -3034,9 +3034,9 @@ heap_delete(Relation relation, ItemPointer tid,
/*
* If we didn't pin the visibility map page and the page has become all
- * visible while we were busy locking the buffer, we'll have to unlock and
- * re-lock, to avoid holding the buffer lock across an I/O. That's a bit
- * unfortunate, but hopefully shouldn't happen often.
+ * visible or all frozen while we were busy locking the buffer, we'll
+ * have to unlock and re-lock, to avoid holding the buffer lock across an
+ * I/O. That's a bit unfortunate, but hopefully shouldn't happen often.
*/
if (vmbuffer == InvalidBuffer && PageIsAllVisible(page))
{
@@ -7205,7 +7205,7 @@ log_heap_freeze(Relation reln, Buffer buffer, TransactionId cutoff_xid,
*/
XLogRecPtr
log_heap_visible(RelFileNode rnode, Buffer heap_buffer, Buffer vm_buffer,
- TransactionId cutoff_xid)
+ TransactionId cutoff_xid, uint8 vmflags)
{
xl_heap_visible xlrec;
XLogRecPtr recptr;
@@ -7215,6 +7215,7 @@ log_heap_visible(RelFileNode rnode, Buffer heap_buffer, Buffer vm_buffer,
Assert(BufferIsValid(vm_buffer));
xlrec.cutoff_xid = cutoff_xid;
+ xlrec.flags = vmflags;
XLogBeginInsert();
XLogRegisterData((char *) &xlrec, SizeOfHeapVisible);
@@ -7804,7 +7805,12 @@ heap_xlog_visible(XLogReaderState *record)
* the subsequent update won't be replayed to clear the flag.
*/
page = BufferGetPage(buffer);
- PageSetAllVisible(page);
+
+ if (xlrec->flags & VISIBILITYMAP_ALL_VISIBLE)
+ PageSetAllVisible(page);
+ if (xlrec->flags & VISIBILITYMAP_ALL_FROZEN)
+ PageSetAllFrozen(page);
+
MarkBufferDirty(buffer);
}
else if (action == BLK_RESTORED)
@@ -7856,7 +7862,7 @@ heap_xlog_visible(XLogReaderState *record)
*/
if (lsn > PageGetLSN(vmpage))
visibilitymap_set(reln, blkno, InvalidBuffer, lsn, vmbuffer,
- xlrec->cutoff_xid);
+ xlrec->cutoff_xid, xlrec->flags);
ReleaseBuffer(vmbuffer);
FreeFakeRelcacheEntry(reln);
diff --git a/src/backend/access/heap/hio.c b/src/backend/access/heap/hio.c
index 6db73bf..0fe49eb 100644
--- a/src/backend/access/heap/hio.c
+++ b/src/backend/access/heap/hio.c
@@ -119,7 +119,7 @@ ReadBufferBI(Relation relation, BlockNumber targetBlock,
* be less than buffer2.
*/
static void
-GetVisibilityMapPins(Relation relation, Buffer buffer1, Buffer buffer2,
+GetVisibilitymapPins(Relation relation, Buffer buffer1, Buffer buffer2,
BlockNumber block1, BlockNumber block2,
Buffer *vmbuffer1, Buffer *vmbuffer2)
{
@@ -380,11 +380,11 @@ RelationGetBufferForTuple(Relation relation, Size len,
* done.
*/
if (otherBuffer == InvalidBuffer || buffer <= otherBuffer)
- GetVisibilityMapPins(relation, buffer, otherBuffer,
+ GetVisibilitymapPins(relation, buffer, otherBuffer,
targetBlock, otherBlock, vmbuffer,
vmbuffer_other);
else
- GetVisibilityMapPins(relation, otherBuffer, buffer,
+ GetVisibilitymapPins(relation, otherBuffer, buffer,
otherBlock, targetBlock, vmbuffer_other,
vmbuffer);
diff --git a/src/backend/access/heap/visibilitymap.c b/src/backend/access/heap/visibilitymap.c
index 7c38772..387a0d6 100644
--- a/src/backend/access/heap/visibilitymap.c
+++ b/src/backend/access/heap/visibilitymap.c
@@ -15,39 +15,46 @@
* visibilitymap_pin - pin a map page for setting a bit
* visibilitymap_pin_ok - check whether correct map page is already pinned
* visibilitymap_set - set a bit in a previously pinned page
- * visibilitymap_test - test if a bit is set
+ * visibilitymap_get_status - get status of bits
* visibilitymap_count - count number of bits set in visibility map
* visibilitymap_truncate - truncate the visibility map
*
* NOTES
*
- * The visibility map is a bitmap with one bit per heap page. A set bit means
- * that all tuples on the page are known visible to all transactions, and
- * therefore the page doesn't need to be vacuumed. The map is conservative in
- * the sense that we make sure that whenever a bit is set, we know the
- * condition is true, but if a bit is not set, it might or might not be true.
+ * The visibility map is a bitmap with two bits (all-visible and all-frozen)
+ * per heap page. A set all-visible bit means that all tuples on the page are
+ * known visible to all transactions, and therefore the page doesn't need to
+ * be vacuumed. A set all-frozen bit means that all tuples on the page are
+ * completely frozen, and therefore the page doesn't need to be vacuumed even
+ * if whole table scanning vacuum is required (e.g. anti-wraparound vacuum).
+ * The all-frozen bit must be set only when the page is already all-visible.
+ *
+ * The map is conservative in the sense that we make sure that whenever a bit
+ * is set, we know the condition is true, but if a bit is not set, it might or
+ * might not be true.
*
* Clearing a visibility map bit is not separately WAL-logged. The callers
* must make sure that whenever a bit is cleared, the bit is cleared on WAL
- * replay of the updating operation as well.
+ * replay of the updating operation as well. And all-frozen bit must be
+ * cleared with all-visible at the same time.
*
* When we *set* a visibility map during VACUUM, we must write WAL. This may
* seem counterintuitive, since the bit is basically a hint: if it is clear,
- * it may still be the case that every tuple on the page is visible to all
- * transactions; we just don't know that for certain. The difficulty is that
- * there are two bits which are typically set together: the PD_ALL_VISIBLE bit
- * on the page itself, and the visibility map bit. If a crash occurs after the
- * visibility map page makes it to disk and before the updated heap page makes
- * it to disk, redo must set the bit on the heap page. Otherwise, the next
- * insert, update, or delete on the heap page will fail to realize that the
- * visibility map bit must be cleared, possibly causing index-only scans to
- * return wrong answers.
+ * it may still be the case that every tuple on the page is all-visible or
+ * all-frozen we just don't know that for certain. The difficulty is that
+ * there are two bits which are typically set together: the PD_ALL_VISIBLE
+ * or PD_ALL_FROZEN bit on the page itself, and the corresponding visibility map
+ * bit. If a crash occurs after the visibility map page makes it to disk and before
+ * the updated heap page makes it to disk, redo must set the bit on the heap page.
+ * Otherwise, the next insert, update, or delete on the heap page will fail to
+ * realize that the visibility map bit must be cleared, possibly causing index-only
+ * scans to return wrong answers.
*
* VACUUM will normally skip pages for which the visibility map bit is set;
* such pages can't contain any dead tuples and therefore don't need vacuuming.
- * The visibility map is not used for anti-wraparound vacuums, because
- * an anti-wraparound vacuum needs to freeze tuples and observe the latest xid
- * present in the table, even on pages that don't have any dead tuples.
+ * The visibility map has the all-frozen bit which indicates all tuples on
+ * corresponding page has been completely frozen, so the visibility map is also
+ * used for anti-wraparound vacuum, even if freezing of tuples is required.
*
* LOCKING
*
@@ -58,14 +65,14 @@
* section that logs the page modification. However, we don't want to hold
* the buffer lock over any I/O that may be required to read in the visibility
* map page. To avoid this, we examine the heap page before locking it;
- * if the page-level PD_ALL_VISIBLE bit is set, we pin the visibility map
- * bit. Then, we lock the buffer. But this creates a race condition: there
- * is a possibility that in the time it takes to lock the buffer, the
- * PD_ALL_VISIBLE bit gets set. If that happens, we have to unlock the
- * buffer, pin the visibility map page, and relock the buffer. This shouldn't
- * happen often, because only VACUUM currently sets visibility map bits,
- * and the race will only occur if VACUUM processes a given page at almost
- * exactly the same time that someone tries to further modify it.
+ * if the page-level PD_ALL_VISIBLE or PD_ALL_FROZEN bit is set, we pin the
+ * visibility map bit. Then, we lock the buffer. But this creates a race
+ * condition: there is a possibility that in the time it takes to lock the
+ * buffer, the PD_ALL_VISIBLE or PD_ALL_FROZEN bit gets set. If that happens,
+ * we have to unlock the buffer, pin the visibility map page, and relock the
+ * buffer. This shouldn't happen often, because only VACUUM currently sets
+ * visibility map bits, and the race will only occur if VACUUM processes a given
+ * page at almost exactly the same time that someone tries to further modify it.
*
* To set a bit, you need to hold a lock on the heap page. That prevents
* the race condition where VACUUM sees that all tuples on the page are
@@ -101,11 +108,14 @@
*/
#define MAPSIZE (BLCKSZ - MAXALIGN(SizeOfPageHeaderData))
-/* Number of bits allocated for each heap block. */
-#define BITS_PER_HEAPBLOCK 1
+/*
+ * Number of bits allocated for each heap block.
+ * One for all-visible, other for all-frozen.
+*/
+#define BITS_PER_HEAPBLOCK 2
/* Number of heap blocks we can represent in one byte. */
-#define HEAPBLOCKS_PER_BYTE 8
+#define HEAPBLOCKS_PER_BYTE 4
/* Number of heap blocks we can represent in one visibility map page. */
#define HEAPBLOCKS_PER_PAGE (MAPSIZE * HEAPBLOCKS_PER_BYTE)
@@ -113,26 +123,44 @@
/* Mapping from heap block number to the right bit in the visibility map */
#define HEAPBLK_TO_MAPBLOCK(x) ((x) / HEAPBLOCKS_PER_PAGE)
#define HEAPBLK_TO_MAPBYTE(x) (((x) % HEAPBLOCKS_PER_PAGE) / HEAPBLOCKS_PER_BYTE)
-#define HEAPBLK_TO_MAPBIT(x) ((x) % HEAPBLOCKS_PER_BYTE)
-
-/* table for fast counting of set bits */
-static const uint8 number_of_ones[256] = {
- 0, 1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3, 4,
- 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
- 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
- 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
- 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
- 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
- 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
- 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
- 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
- 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
- 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
- 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
- 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
- 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
- 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
- 4, 5, 5, 6, 5, 6, 6, 7, 5, 6, 6, 7, 6, 7, 7, 8
+#define HEAPBLK_TO_MAPBIT(x) (((x) % HEAPBLOCKS_PER_BYTE) * BITS_PER_HEAPBLOCK)
+
+/* tables for fast counting of set bits for visible and freeze */
+static const uint8 number_of_ones_for_visible[256] = {
+ 0, 1, 0, 1, 1, 2, 1, 2, 0, 1, 0, 1, 1, 2, 1, 2,
+ 1, 2, 1, 2, 2, 3, 2, 3, 1, 2, 1, 2, 2, 3, 2, 3,
+ 0, 1, 0, 1, 1, 2, 1, 2, 0, 1, 0, 1, 1, 2, 1, 2,
+ 1, 2, 1, 2, 2, 3, 2, 3, 1, 2, 1, 2, 2, 3, 2, 3,
+ 1, 2, 1, 2, 2, 3, 2, 3, 1, 2, 1, 2, 2, 3, 2, 3,
+ 2, 3, 2, 3, 3, 4, 3, 4, 2, 3, 2, 3, 3, 4, 3, 4,
+ 1, 2, 1, 2, 2, 3, 2, 3, 1, 2, 1, 2, 2, 3, 2, 3,
+ 2, 3, 2, 3, 3, 4, 3, 4, 2, 3, 2, 3, 3, 4, 3, 4,
+ 0, 1, 0, 1, 1, 2, 1, 2, 0, 1, 0, 1, 1, 2, 1, 2,
+ 1, 2, 1, 2, 2, 3, 2, 3, 1, 2, 1, 2, 2, 3, 2, 3,
+ 0, 1, 0, 1, 1, 2, 1, 2, 0, 1, 0, 1, 1, 2, 1, 2,
+ 1, 2, 1, 2, 2, 3, 2, 3, 1, 2, 1, 2, 2, 3, 2, 3,
+ 1, 2, 1, 2, 2, 3, 2, 3, 1, 2, 1, 2, 2, 3, 2, 3,
+ 2, 3, 2, 3, 3, 4, 3, 4, 2, 3, 2, 3, 3, 4, 3, 4,
+ 1, 2, 1, 2, 2, 3, 2, 3, 1, 2, 1, 2, 2, 3, 2, 3,
+ 2, 3, 2, 3, 3, 4, 3, 4, 2, 3, 2, 3, 3, 4, 3, 4
+};
+static const uint8 number_of_ones_for_frozen[256] = {
+ 0, 0, 1, 1, 0, 0, 1, 1, 1, 1, 2, 2, 1, 1, 2, 2,
+ 0, 0, 1, 1, 0, 0, 1, 1, 1, 1, 2, 2, 1, 1, 2, 2,
+ 1, 1, 2, 2, 1, 1, 2, 2, 2, 2, 3, 3, 2, 2, 3, 3,
+ 1, 1, 2, 2, 1, 1, 2, 2, 2, 2, 3, 3, 2, 2, 3, 3,
+ 0, 0, 1, 1, 0, 0, 1, 1, 1, 1, 2, 2, 1, 1, 2, 2,
+ 0, 0, 1, 1, 0, 0, 1, 1, 1, 1, 2, 2, 1, 1, 2, 2,
+ 1, 1, 2, 2, 1, 1, 2, 2, 2, 2, 3, 3, 2, 2, 3, 3,
+ 1, 1, 2, 2, 1, 1, 2, 2, 2, 2, 3, 3, 2, 2, 3, 3,
+ 1, 1, 2, 2, 1, 1, 2, 2, 2, 2, 3, 3, 2, 2, 3, 3,
+ 1, 1, 2, 2, 1, 1, 2, 2, 2, 2, 3, 3, 2, 2, 3, 3,
+ 2, 2, 3, 3, 2, 2, 3, 3, 3, 3, 4, 4, 3, 3, 4, 4,
+ 2, 2, 3, 3, 2, 2, 3, 3, 3, 3, 4, 4, 3, 3, 4, 4,
+ 1, 1, 2, 2, 1, 1, 2, 2, 2, 2, 3, 3, 2, 2, 3, 3,
+ 1, 1, 2, 2, 1, 1, 2, 2, 2, 2, 3, 3, 2, 2, 3, 3,
+ 2, 2, 3, 3, 2, 2, 3, 3, 3, 3, 4, 4, 3, 3, 4, 4,
+ 2, 2, 3, 3, 2, 2, 3, 3, 3, 3, 4, 4, 3, 3, 4, 4
};
/* prototypes for internal routines */
@@ -141,7 +169,7 @@ static void vm_extend(Relation rel, BlockNumber nvmblocks);
/*
- * visibilitymap_clear - clear a bit in visibility map
+ * visibilitymap_clear - clear all bits in visibility map
*
* You must pass a buffer containing the correct map page to this function.
* Call visibilitymap_pin first to pin the right one. This function doesn't do
@@ -153,11 +181,11 @@ visibilitymap_clear(Relation rel, BlockNumber heapBlk, Buffer buf)
BlockNumber mapBlock = HEAPBLK_TO_MAPBLOCK(heapBlk);
int mapByte = HEAPBLK_TO_MAPBYTE(heapBlk);
int mapBit = HEAPBLK_TO_MAPBIT(heapBlk);
- uint8 mask = 1 << mapBit;
+ uint8 mask = VISIBILITYMAP_VALID_BITS << mapBit;
char *map;
#ifdef TRACE_VISIBILITYMAP
- elog(DEBUG1, "vm_clear %s %d", RelationGetRelationName(rel), heapBlk);
+ elog(DEBUG1, "vm_clear %s block %d", RelationGetRelationName(rel), heapBlk);
#endif
if (!BufferIsValid(buf) || BufferGetBlockNumber(buf) != mapBlock)
@@ -186,7 +214,7 @@ visibilitymap_clear(Relation rel, BlockNumber heapBlk, Buffer buf)
* visibilitymap_set to actually set the bit.
*
* On entry, *buf should be InvalidBuffer or a valid buffer returned by
- * an earlier call to visibilitymap_pin or visibilitymap_test on the same
+ * an earlier call to visibilitymap_pin or visibilitymap_get_status on the same
* relation. On return, *buf is a valid buffer with the map page containing
* the bit for heapBlk.
*
@@ -212,7 +240,7 @@ visibilitymap_pin(Relation rel, BlockNumber heapBlk, Buffer *buf)
* visibilitymap_pin_ok - do we already have the correct page pinned?
*
* On entry, buf should be InvalidBuffer or a valid buffer returned by
- * an earlier call to visibilitymap_pin or visibilitymap_test on the same
+ * an earlier call to visibilitymap_pin or visibilitymap_get_status on the same
* relation. The return value indicates whether the buffer covers the
* given heapBlk.
*/
@@ -225,7 +253,7 @@ visibilitymap_pin_ok(BlockNumber heapBlk, Buffer buf)
}
/*
- * visibilitymap_set - set a bit on a previously pinned page
+ * visibilitymap_set - set bit(s) on a previously pinned page
*
* recptr is the LSN of the XLOG record we're replaying, if we're in recovery,
* or InvalidXLogRecPtr in normal running. The page LSN is advanced to the
@@ -234,10 +262,11 @@ visibilitymap_pin_ok(BlockNumber heapBlk, Buffer buf)
* marked all-visible; it is needed for Hot Standby, and can be
* InvalidTransactionId if the page contains no tuples.
*
- * Caller is expected to set the heap page's PD_ALL_VISIBLE bit before calling
- * this function. Except in recovery, caller should also pass the heap
- * buffer. When checksums are enabled and we're not in recovery, we must add
- * the heap buffer to the WAL chain to protect it from being torn.
+ * Caller is expected to set the heap page's PD_ALL_VISIBLE or PD_ALL_FROZEN
+ * bit before calling this function. Except in recovery, caller should also
+ * pass the heap buffer and flags which indicates what flag we want to set.
+ * When checksums are enabled and we're not in recovery, we must add the heap
+ * buffer to the WAL chain to protect it from being torn.
*
* You must pass a buffer containing the correct map page to this function.
* Call visibilitymap_pin first to pin the right one. This function doesn't do
@@ -245,7 +274,8 @@ visibilitymap_pin_ok(BlockNumber heapBlk, Buffer buf)
*/
void
visibilitymap_set(Relation rel, BlockNumber heapBlk, Buffer heapBuf,
- XLogRecPtr recptr, Buffer vmBuf, TransactionId cutoff_xid)
+ XLogRecPtr recptr, Buffer vmBuf, TransactionId cutoff_xid,
+ uint8 flags)
{
BlockNumber mapBlock = HEAPBLK_TO_MAPBLOCK(heapBlk);
uint32 mapByte = HEAPBLK_TO_MAPBYTE(heapBlk);
@@ -254,11 +284,12 @@ visibilitymap_set(Relation rel, BlockNumber heapBlk, Buffer heapBuf,
char *map;
#ifdef TRACE_VISIBILITYMAP
- elog(DEBUG1, "vm_set %s %d", RelationGetRelationName(rel), heapBlk);
+ elog(DEBUG1, "vm_set %s block %d, flag %u", RelationGetRelationName(rel), heapBlk, flags);
#endif
Assert(InRecovery || XLogRecPtrIsInvalid(recptr));
Assert(InRecovery || BufferIsValid(heapBuf));
+ Assert(flags & VISIBILITYMAP_VALID_BITS);
/* Check that we have the right heap page pinned, if present */
if (BufferIsValid(heapBuf) && BufferGetBlockNumber(heapBuf) != heapBlk)
@@ -272,11 +303,11 @@ visibilitymap_set(Relation rel, BlockNumber heapBlk, Buffer heapBuf,
map = PageGetContents(page);
LockBuffer(vmBuf, BUFFER_LOCK_EXCLUSIVE);
- if (!(map[mapByte] & (1 << mapBit)))
+ if (flags != (map[mapByte] & (flags << mapBit)))
{
START_CRIT_SECTION();
- map[mapByte] |= (1 << mapBit);
+ map[mapByte] |= (flags << mapBit);
MarkBufferDirty(vmBuf);
if (RelationNeedsWAL(rel))
@@ -285,7 +316,7 @@ visibilitymap_set(Relation rel, BlockNumber heapBlk, Buffer heapBuf,
{
Assert(!InRecovery);
recptr = log_heap_visible(rel->rd_node, heapBuf, vmBuf,
- cutoff_xid);
+ cutoff_xid, flags);
/*
* If data checksums are enabled (or wal_log_hints=on), we
@@ -295,11 +326,16 @@ visibilitymap_set(Relation rel, BlockNumber heapBlk, Buffer heapBuf,
{
Page heapPage = BufferGetPage(heapBuf);
- /* caller is expected to set PD_ALL_VISIBLE first */
- Assert(PageIsAllVisible(heapPage));
+ /*
+ * Caller is expected to set PD_ALL_VISIBLE or
+ * PD_ALL_FROZEN first.
+ */
+ Assert(((flags | VISIBILITYMAP_ALL_VISIBLE) && PageIsAllVisible(heapPage)) ||
+ ((flags | VISIBILITYMAP_ALL_FROZEN) && PageIsAllFrozen(heapPage)));
PageSetLSN(heapPage, recptr);
}
}
+
PageSetLSN(page, recptr);
}
@@ -310,15 +346,17 @@ visibilitymap_set(Relation rel, BlockNumber heapBlk, Buffer heapBuf,
}
/*
- * visibilitymap_test - test if a bit is set
+ * visibilitymap_get_status - get status of bits
*
- * Are all tuples on heapBlk visible to all, according to the visibility map?
+ * Are all tuples on heapBlk visible to all or are marked frozen, according
+ * to the visibility map?
*
* On entry, *buf should be InvalidBuffer or a valid buffer returned by an
- * earlier call to visibilitymap_pin or visibilitymap_test on the same
+ * earlier call to visibilitymap_pin or visibilitymap_get_status on the same
* relation. On return, *buf is a valid buffer with the map page containing
* the bit for heapBlk, or InvalidBuffer. The caller is responsible for
- * releasing *buf after it's done testing and setting bits.
+ * releasing *buf after it's done testing and setting bits, and must pass flags
+ * for which it needs to check the value in visibility map.
*
* NOTE: This function is typically called without a lock on the heap page,
* so somebody else could change the bit just after we look at it. In fact,
@@ -327,17 +365,16 @@ visibilitymap_set(Relation rel, BlockNumber heapBlk, Buffer heapBuf,
* we might see the old value. It is the caller's responsibility to deal with
* all concurrency issues!
*/
-bool
-visibilitymap_test(Relation rel, BlockNumber heapBlk, Buffer *buf)
+uint8
+visibilitymap_get_status(Relation rel, BlockNumber heapBlk, Buffer *buf)
{
BlockNumber mapBlock = HEAPBLK_TO_MAPBLOCK(heapBlk);
uint32 mapByte = HEAPBLK_TO_MAPBYTE(heapBlk);
uint8 mapBit = HEAPBLK_TO_MAPBIT(heapBlk);
- bool result;
char *map;
#ifdef TRACE_VISIBILITYMAP
- elog(DEBUG1, "vm_test %s %d", RelationGetRelationName(rel), heapBlk);
+ elog(DEBUG1, "vm_get_status %s, block %d", RelationGetRelationName(rel), heapBlk);
#endif
/* Reuse the old pinned buffer if possible */
@@ -360,13 +397,11 @@ visibilitymap_test(Relation rel, BlockNumber heapBlk, Buffer *buf)
map = PageGetContents(BufferGetPage(*buf));
/*
- * A single-bit read is atomic. There could be memory-ordering effects
+ * The double bits read is atomic. There could be memory-ordering effects
* here, but for performance reasons we make it the caller's job to worry
* about that.
*/
- result = (map[mapByte] & (1 << mapBit)) ? true : false;
-
- return result;
+ return ((map[mapByte] >> mapBit) & VISIBILITYMAP_VALID_BITS);
}
/*
@@ -374,13 +409,17 @@ visibilitymap_test(Relation rel, BlockNumber heapBlk, Buffer *buf)
*
* Note: we ignore the possibility of race conditions when the table is being
* extended concurrently with the call. New pages added to the table aren't
- * going to be marked all-visible, so they won't affect the result.
+ * going to be marked all-visible or all-frozen, so they won't affect the result.
+ * The caller must set the flags which indicates what flag we want to count.
*/
BlockNumber
-visibilitymap_count(Relation rel)
+visibilitymap_count(Relation rel, BlockNumber *all_frozen)
{
- BlockNumber result = 0;
BlockNumber mapBlock;
+ BlockNumber all_visible = 0;
+
+ if (all_frozen)
+ *all_frozen = 0;
for (mapBlock = 0;; mapBlock++)
{
@@ -406,13 +445,15 @@ visibilitymap_count(Relation rel)
for (i = 0; i < MAPSIZE; i++)
{
- result += number_of_ones[map[i]];
+ all_visible += number_of_ones_for_visible[map[i]];
+ if (all_frozen)
+ *all_frozen += number_of_ones_for_frozen[map[i]];
}
ReleaseBuffer(mapBuffer);
}
- return result;
+ return all_visible;
}
/*
@@ -435,7 +476,7 @@ visibilitymap_truncate(Relation rel, BlockNumber nheapblocks)
uint8 truncBit = HEAPBLK_TO_MAPBIT(nheapblocks);
#ifdef TRACE_VISIBILITYMAP
- elog(DEBUG1, "vm_truncate %s %d", RelationGetRelationName(rel), nheapblocks);
+ elog(DEBUG1, "vm_truncate %s block %d", RelationGetRelationName(rel), nheapblocks);
#endif
RelationOpenSmgr(rel);
diff --git a/src/backend/catalog/index.c b/src/backend/catalog/index.c
index e59b163..1cea026 100644
--- a/src/backend/catalog/index.c
+++ b/src/backend/catalog/index.c
@@ -1813,7 +1813,7 @@ FormIndexDatum(IndexInfo *indexInfo,
* isprimary: if true, set relhaspkey true; else no change
* reltuples: if >= 0, set reltuples to this value; else no change
*
- * If reltuples >= 0, relpages and relallvisible are also updated (using
+ * If reltuples >= 0, relpages, relallvisible are also updated (using
* RelationGetNumberOfBlocks() and visibilitymap_count()).
*
* NOTE: an important side-effect of this operation is that an SI invalidation
@@ -1921,7 +1921,7 @@ index_update_stats(Relation rel,
BlockNumber relallvisible;
if (rd_rel->relkind != RELKIND_INDEX)
- relallvisible = visibilitymap_count(rel);
+ relallvisible = visibilitymap_count(rel, NULL);
else /* don't bother for indexes */
relallvisible = 0;
diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index ccc030f..8c555eb 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -444,6 +444,7 @@ CREATE VIEW pg_stat_all_tables AS
pg_stat_get_live_tuples(C.oid) AS n_live_tup,
pg_stat_get_dead_tuples(C.oid) AS n_dead_tup,
pg_stat_get_mod_since_analyze(C.oid) AS n_mod_since_analyze,
+ pg_stat_get_frozen_pages(C.oid) AS n_frozen_page,
pg_stat_get_last_vacuum_time(C.oid) as last_vacuum,
pg_stat_get_last_autovacuum_time(C.oid) as last_autovacuum,
pg_stat_get_last_analyze_time(C.oid) as last_analyze,
diff --git a/src/backend/commands/analyze.c b/src/backend/commands/analyze.c
index ddb68ab..02a2c68 100644
--- a/src/backend/commands/analyze.c
+++ b/src/backend/commands/analyze.c
@@ -314,6 +314,8 @@ do_analyze_rel(Relation onerel, int options, VacuumParams *params,
Oid save_userid;
int save_sec_context;
int save_nestlevel;
+ BlockNumber relallvisible,
+ relallfrozen;
if (inh)
ereport(elevel,
@@ -564,6 +566,10 @@ do_analyze_rel(Relation onerel, int options, VacuumParams *params,
}
}
+ /* Calculate the number of all-visible and all-frozen bit */
+ if (!inh)
+ relallvisible = visibilitymap_count(onerel, &relallfrozen);
+
/*
* Update pages/tuples stats in pg_class ... but not if we're doing
* inherited stats.
@@ -572,7 +578,7 @@ do_analyze_rel(Relation onerel, int options, VacuumParams *params,
vac_update_relstats(onerel,
relpages,
totalrows,
- visibilitymap_count(onerel),
+ relallvisible,
hasindex,
InvalidTransactionId,
InvalidMultiXactId,
@@ -608,7 +614,7 @@ do_analyze_rel(Relation onerel, int options, VacuumParams *params,
* tracks per-table stats.
*/
if (!inh)
- pgstat_report_analyze(onerel, totalrows, totaldeadrows);
+ pgstat_report_analyze(onerel, totalrows, totaldeadrows, relallfrozen);
/* If this isn't part of VACUUM ANALYZE, let index AMs do cleanup */
if (!(options & VACOPT_VACUUM))
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 7c4ef58..0a02a25 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -729,11 +729,11 @@ vac_estimate_reltuples(Relation relation, bool is_analyze,
* marked with xmin = our xid.
*
* In addition to fundamentally nontransactional statistics such as
- * relpages and relallvisible, we try to maintain certain lazily-updated
- * DDL flags such as relhasindex, by clearing them if no longer correct.
- * It's safe to do this in VACUUM, which can't run in parallel with
- * CREATE INDEX/RULE/TRIGGER and can't be part of a transaction block.
- * However, it's *not* safe to do it in an ANALYZE that's within an
+ * relpages, relallvisible, we try to maintain certain lazily-updated
+ * DDL flags such as relhasindex, by clearing them if no onger correct.
+ * It's safe to do this in VACUUM, which can't run in
+ * parallel with CREATE INDEX/RULE/TRIGGER and can't be part of a transaction
+ * block. However, it's *not* safe to do it in an ANALYZE that's within an
* outer transaction, because for example the current transaction might
* have dropped the last index; then we'd think relhasindex should be
* cleared, but if the transaction later rolls back this would be wrong.
diff --git a/src/backend/commands/vacuumlazy.c b/src/backend/commands/vacuumlazy.c
index 2429889..994efb7 100644
--- a/src/backend/commands/vacuumlazy.c
+++ b/src/backend/commands/vacuumlazy.c
@@ -106,6 +106,8 @@ typedef struct LVRelStats
BlockNumber rel_pages; /* total number of pages */
BlockNumber scanned_pages; /* number of pages we examined */
BlockNumber pinskipped_pages; /* # of pages we skipped due to a pin */
+ BlockNumber vmskipped_frozen_pages; /* # of pages we skipped by all-frozen bit
+ of visibility map */
double scanned_tuples; /* counts only tuples on scanned pages */
double old_rel_tuples; /* previous value of pg_class.reltuples */
double new_rel_tuples; /* new estimated total # of tuples */
@@ -156,7 +158,7 @@ static void lazy_record_dead_tuple(LVRelStats *vacrelstats,
static bool lazy_tid_reaped(ItemPointer itemptr, void *state);
static int vac_cmp_itemptr(const void *left, const void *right);
static bool heap_page_is_all_visible(Relation rel, Buffer buf,
- TransactionId *visibility_cutoff_xid);
+ TransactionId *visibility_cutoff_xid, bool *all_frozen);
/*
@@ -188,7 +190,8 @@ lazy_vacuum_rel(Relation onerel, int options, VacuumParams *params,
MultiXactId mxactFullScanLimit;
BlockNumber new_rel_pages;
double new_rel_tuples;
- BlockNumber new_rel_allvisible;
+ BlockNumber new_rel_allvisible,
+ new_rel_allfrozen;
double new_live_tuples;
TransactionId new_frozen_xid;
MultiXactId new_min_multi;
@@ -221,7 +224,8 @@ lazy_vacuum_rel(Relation onerel, int options, VacuumParams *params,
* We request a full scan if either the table's frozen Xid is now older
* than or equal to the requested Xid full-table scan limit; or if the
* table's minimum MultiXactId is older than or equal to the requested
- * mxid full-table scan limit.
+ * mxid full-table scan limit. During full scan, we could skip some pags
+ * according to all-frozen bit of visibility map.
*/
scan_all = TransactionIdPrecedesOrEquals(onerel->rd_rel->relfrozenxid,
xidFullScanLimit);
@@ -253,7 +257,8 @@ lazy_vacuum_rel(Relation onerel, int options, VacuumParams *params,
* NB: We need to check this before truncating the relation, because that
* will change ->rel_pages.
*/
- if (vacrelstats->scanned_pages < vacrelstats->rel_pages)
+ if ((vacrelstats->scanned_pages + vacrelstats->vmskipped_frozen_pages)
+ < vacrelstats->rel_pages)
{
Assert(!scan_all);
scanned_all = false;
@@ -301,10 +306,13 @@ lazy_vacuum_rel(Relation onerel, int options, VacuumParams *params,
new_rel_tuples = vacrelstats->old_rel_tuples;
}
- new_rel_allvisible = visibilitymap_count(onerel);
+ new_rel_allvisible = visibilitymap_count(onerel, &new_rel_allfrozen);
if (new_rel_allvisible > new_rel_pages)
new_rel_allvisible = new_rel_pages;
+ if (new_rel_allfrozen > new_rel_pages)
+ new_rel_allfrozen = new_rel_pages;
+
new_frozen_xid = scanned_all ? FreezeLimit : InvalidTransactionId;
new_min_multi = scanned_all ? MultiXactCutoff : InvalidMultiXactId;
@@ -325,7 +333,8 @@ lazy_vacuum_rel(Relation onerel, int options, VacuumParams *params,
pgstat_report_vacuum(RelationGetRelid(onerel),
onerel->rd_rel->relisshared,
new_live_tuples,
- vacrelstats->new_dead_tuples);
+ vacrelstats->new_dead_tuples,
+ new_rel_allfrozen);
/* and log the action if appropriate */
if (IsAutoVacuumWorkerProcess() && params->log_min_duration >= 0)
@@ -360,10 +369,11 @@ lazy_vacuum_rel(Relation onerel, int options, VacuumParams *params,
get_namespace_name(RelationGetNamespace(onerel)),
RelationGetRelationName(onerel),
vacrelstats->num_index_scans);
- appendStringInfo(&buf, _("pages: %u removed, %u remain, %u skipped due to pins\n"),
+ appendStringInfo(&buf, _("pages: %u removed, %u remain, %u skipped due to pins, %u skipped according to vm\n"),
vacrelstats->pages_removed,
vacrelstats->rel_pages,
- vacrelstats->pinskipped_pages);
+ vacrelstats->pinskipped_pages,
+ vacrelstats->vmskipped_frozen_pages);
appendStringInfo(&buf,
_("tuples: %.0f removed, %.0f remain, %.0f are dead but not yet removable\n"),
vacrelstats->tuples_deleted,
@@ -486,9 +496,12 @@ lazy_scan_heap(Relation onerel, LVRelStats *vacrelstats,
* consecutive pages. Since we're reading sequentially, the OS should be
* doing readahead for us, so there's no gain in skipping a page now and
* then; that's likely to disable readahead and so be counterproductive.
- * Also, skipping even a single page means that we can't update
- * relfrozenxid, so we only want to do it if we can skip a goodly number
- * of pages.
+ * Also, skipping even a single page accorinding to all-visible bit of
+ * visibility map means that we can't update relfrozenxid, so we only want
+ * to do it if we can skip a goodly number. On the other hand, we count
+ * both how many pages we skipped according to all-frozen bit of visibility
+ * map and how many pages we freeze, so we can update relfrozenxid if
+ * the sum of two is as many as pages of table.
*
* Before entering the main loop, establish the invariant that
* next_not_all_visible_block is the next block number >= blkno that's not
@@ -498,24 +511,24 @@ lazy_scan_heap(Relation onerel, LVRelStats *vacrelstats,
* started skipping blocks, we may as well skip everything up to the next
* not-all-visible block.
*
- * Note: if scan_all is true, we won't actually skip any pages; but we
+ * Note: if scan_all is true, we might not actually skip any pages; but we
* maintain next_not_all_visible_block anyway, so as to set up the
* all_visible_according_to_vm flag correctly for each page.
*
- * Note: The value returned by visibilitymap_test could be slightly
+ * Note: The value returned by visibilitymap_get_status could be slightly
* out-of-date, since we make this test before reading the corresponding
* heap page or locking the buffer. This is OK. If we mistakenly think
- * that the page is all-visible when in fact the flag's just been cleared,
- * we might fail to vacuum the page. But it's OK to skip pages when
- * scan_all is not set, so no great harm done; the next vacuum will find
- * them. If we make the reverse mistake and vacuum a page unnecessarily,
- * it'll just be a no-op.
+ * that the page is all-visible/all-frozen when in fact the flag's just
+ * been cleared, we might fail to vacuum the page. But it's OK to skip
+ * pages when scan_all is not set, so no great harm done; the next vacuum
+ * will find them. If we make the reverse mistake and vacuum a page
+ * unnecessarily, it'll just be a no-op.
*/
for (next_not_all_visible_block = 0;
next_not_all_visible_block < nblocks;
next_not_all_visible_block++)
{
- if (!visibilitymap_test(onerel, next_not_all_visible_block, &vmbuffer))
+ if (!VM_ALL_VISIBLE(onerel, next_not_all_visible_block, &vmbuffer))
break;
vacuum_delay_point();
}
@@ -533,9 +546,13 @@ lazy_scan_heap(Relation onerel, LVRelStats *vacrelstats,
bool tupgone,
hastup;
int prev_dead_count;
- int nfrozen;
+ int nfrozen; /* # of tuples is frozen */
+ int nalready_frozen; /* # of tuples is already frozen */
+ int ntotal_frozen; /* # of frozen tuples in single page */
+ int ntup_per_page;
Size freespace;
bool all_visible_according_to_vm;
+ bool all_frozen_according_to_vm;
bool all_visible;
bool has_dead_tuples;
TransactionId visibility_cutoff_xid = InvalidTransactionId;
@@ -547,8 +564,7 @@ lazy_scan_heap(Relation onerel, LVRelStats *vacrelstats,
next_not_all_visible_block < nblocks;
next_not_all_visible_block++)
{
- if (!visibilitymap_test(onerel, next_not_all_visible_block,
- &vmbuffer))
+ if (!VM_ALL_VISIBLE(onerel, next_not_all_visible_block, &vmbuffer))
break;
vacuum_delay_point();
}
@@ -562,14 +578,29 @@ lazy_scan_heap(Relation onerel, LVRelStats *vacrelstats,
skipping_all_visible_blocks = true;
else
skipping_all_visible_blocks = false;
+
all_visible_according_to_vm = false;
+ all_frozen_according_to_vm = false;
}
else
{
- /* Current block is all-visible */
- if (skipping_all_visible_blocks && !scan_all)
- continue;
+ /*
+ * This block is at least all-visible according to the visibility map.
+ * We check whether this block is all-frozen or not, to skip to
+ * vacuum this page even if scan_all is true.
+ */
+ bool all_frozen = VM_ALL_FROZEN(onerel, blkno, &vmbuffer);
+
+ if (scan_all && all_frozen)
+ {
+ vacrelstats->vmskipped_frozen_pages++;
+ continue;
+ }
+ else if (!scan_all && skipping_all_visible_blocks)
+ continue;
+
all_visible_according_to_vm = true;
+ all_frozen_according_to_vm = all_frozen;
}
vacuum_delay_point();
@@ -716,7 +747,7 @@ lazy_scan_heap(Relation onerel, LVRelStats *vacrelstats,
empty_pages++;
freespace = PageGetHeapFreeSpace(page);
- /* empty pages are always all-visible */
+ /* empty pages are always all-visible and all-frozen */
if (!PageIsAllVisible(page))
{
START_CRIT_SECTION();
@@ -739,8 +770,10 @@ lazy_scan_heap(Relation onerel, LVRelStats *vacrelstats,
log_newpage_buffer(buf, true);
PageSetAllVisible(page);
+ PageSetAllFrozen(page);
visibilitymap_set(onerel, blkno, buf, InvalidXLogRecPtr,
- vmbuffer, InvalidTransactionId);
+ vmbuffer, InvalidTransactionId,
+ VISIBILITYMAP_ALL_VISIBLE | VISIBILITYMAP_ALL_FROZEN);
END_CRIT_SECTION();
}
@@ -764,6 +797,8 @@ lazy_scan_heap(Relation onerel, LVRelStats *vacrelstats,
all_visible = true;
has_dead_tuples = false;
nfrozen = 0;
+ nalready_frozen = 0;
+ ntup_per_page = 0;
hastup = false;
prev_dead_count = vacrelstats->num_dead_tuples;
maxoff = PageGetMaxOffsetNumber(page);
@@ -918,8 +953,13 @@ lazy_scan_heap(Relation onerel, LVRelStats *vacrelstats,
else
{
num_tuples += 1;
+ ntup_per_page += 1;;
hastup = true;
+ /* Check whether this tuple is alrady frozen or not */
+ if (HeapTupleHeaderXminFrozen(tuple.t_data))
+ nalready_frozen += 1;
+
/*
* Each non-removable tuple must be checked to see if it needs
* freezing. Note we already have exclusive buffer lock.
@@ -931,9 +971,9 @@ lazy_scan_heap(Relation onerel, LVRelStats *vacrelstats,
} /* scan along page */
/*
- * If we froze any tuples, mark the buffer dirty, and write a WAL
- * record recording the changes. We must log the changes to be
- * crash-safe against future truncation of CLOG.
+ * If we freeze any tuples, mark the buffer dirty, and write a WAL
+ * record recording the changes. We must log the changes to be crash-safe
+ * against future truncation of CLOG.
*/
if (nfrozen > 0)
{
@@ -966,6 +1006,9 @@ lazy_scan_heap(Relation onerel, LVRelStats *vacrelstats,
END_CRIT_SECTION();
}
+ /* Compute the number of frozen tuples in a page */
+ ntotal_frozen = nfrozen + nalready_frozen;
+
/*
* If there are no indexes then we can vacuum the page right now
* instead of doing a second scan.
@@ -988,26 +1031,46 @@ lazy_scan_heap(Relation onerel, LVRelStats *vacrelstats,
freespace = PageGetHeapFreeSpace(page);
- /* mark page all-visible, if appropriate */
- if (all_visible && !all_visible_according_to_vm)
+ /* This page is all visible */
+ if (all_visible)
{
- /*
- * It should never be the case that the visibility map page is set
- * while the page-level bit is clear, but the reverse is allowed
- * (if checksums are not enabled). Regardless, set the both bits
- * so that we get back in sync.
- *
- * NB: If the heap page is all-visible but the VM bit is not set,
- * we don't need to dirty the heap page. However, if checksums
- * are enabled, we do need to make sure that the heap page is
- * dirtied before passing it to visibilitymap_set(), because it
- * may be logged. Given that this situation should only happen in
- * rare cases after a crash, it is not worth optimizing.
- */
- PageSetAllVisible(page);
- MarkBufferDirty(buf);
- visibilitymap_set(onerel, blkno, buf, InvalidXLogRecPtr,
- vmbuffer, visibility_cutoff_xid);
+ uint8 flags = 0;
+
+ /* mark page all-visible, if appropriate */
+ if (!all_visible_according_to_vm)
+ {
+ /*
+ * It should never be the case that the visibility map page is set
+ * while the page-level bit is clear, but the reverse is allowed
+ * (if checksums are not enabled). Regardless, set the both bits
+ * so that we get back in sync.
+ *
+ * NB: If the heap page is all-visible but the VM bit is not set,
+ * we don't need to dirty the heap page. However, if checksums
+ * are enabled, we do need to make sure that the heap page is
+ * dirtied before passing it to visibilitymap_set(), because it
+ * may be logged. Given that this situation should only happen in
+ * rare cases after a crash, it is not worth optimizing.
+ */
+ PageSetAllVisible(page);
+ flags |= VISIBILITYMAP_ALL_VISIBLE;
+ }
+
+ /* mark page all-frozen, if all tuples are frozen and not marked yet */
+ if ((ntotal_frozen == ntup_per_page) && !all_frozen_according_to_vm)
+ {
+ Assert(PageIsAllVisible(page));
+
+ PageSetAllFrozen(page);
+ flags |= VISIBILITYMAP_ALL_FROZEN;
+ }
+
+ if (flags)
+ {
+ MarkBufferDirty(buf);
+ visibilitymap_set(onerel, blkno, buf, InvalidXLogRecPtr,
+ vmbuffer, visibility_cutoff_xid, flags);
+ }
}
/*
@@ -1018,9 +1081,14 @@ lazy_scan_heap(Relation onerel, LVRelStats *vacrelstats,
* that something bad has happened.
*/
else if (all_visible_according_to_vm && !PageIsAllVisible(page)
- && visibilitymap_test(onerel, blkno, &vmbuffer))
+ && VM_ALL_VISIBLE(onerel, blkno, &vmbuffer))
{
- elog(WARNING, "page is not marked all-visible but visibility map bit is set in relation \"%s\" page %u",
+ /* If the all-frozen is set then all-visible must be set */
+ if (all_frozen_according_to_vm)
+ Assert(VM_ALL_FROZEN(onerel, blkno, &vmbuffer) &&
+ VM_ALL_VISIBLE(onerel, blkno, &vmbuffer));
+
+ elog(WARNING, "page is not marked all-visible (and all-frozen) but visibility map bit(s) is set in relation \"%s\" page %u",
relname, blkno);
visibilitymap_clear(onerel, blkno, vmbuffer);
}
@@ -1028,19 +1096,25 @@ lazy_scan_heap(Relation onerel, LVRelStats *vacrelstats,
/*
* It's possible for the value returned by GetOldestXmin() to move
* backwards, so it's not wrong for us to see tuples that appear to
- * not be visible to everyone yet, while PD_ALL_VISIBLE is already
- * set. The real safe xmin value never moves backwards, but
- * GetOldestXmin() is conservative and sometimes returns a value
+ * not be visible to everyone yet, while PD_ALL_VISIBLE (and PD_ALL_FROZEN)
+ * are already set. The real safe xmin value never moves backwards,
+ * but GetOldestXmin() is conservative and sometimes returns a value
* that's unnecessarily small, so if we see that contradiction it just
* means that the tuples that we think are not visible to everyone yet
- * actually are, and the PD_ALL_VISIBLE flag is correct.
+ * actually are, and the PD_ALL_VISIBLE (and PD_ALL_FROZEN) flags are
+ * correct.
*
* There should never be dead tuples on a page with PD_ALL_VISIBLE
* set, however.
*/
else if (PageIsAllVisible(page) && has_dead_tuples)
{
- elog(WARNING, "page containing dead tuples is marked as all-visible in relation \"%s\" page %u",
+ /* If the all-frozen is set then all-visible must be set */
+ if (PageIsAllFrozen(page))
+ Assert(VM_ALL_FROZEN(onerel, blkno, &vmbuffer) &&
+ VM_ALL_VISIBLE(onerel, blkno, &vmbuffer));
+
+ elog(WARNING, "page containing dead tuples is marked as all-visible (and all-frozen) in relation \"%s\" page %u",
relname, blkno);
PageClearAllVisible(page);
MarkBufferDirty(buf);
@@ -1114,6 +1188,13 @@ lazy_scan_heap(Relation onerel, LVRelStats *vacrelstats,
RelationGetRelationName(onerel),
tups_vacuumed, vacuumed_pages)));
+ /* Report how many frozen pages vacuum skipped according to visibility map */
+ ereport(elevel,
+ (errmsg_plural("skipped %d frozen page according to visibility map",
+ "skipped %d frozen pages according to visibility map",
+ vacrelstats->vmskipped_frozen_pages,
+ vacrelstats->vmskipped_frozen_pages)));
+
/*
* This is pretty messy, but we split it up so that we can skip emitting
* individual parts of the message when not applicable.
@@ -1230,6 +1311,7 @@ lazy_vacuum_page(Relation onerel, BlockNumber blkno, Buffer buffer,
OffsetNumber unused[MaxOffsetNumber];
int uncnt = 0;
TransactionId visibility_cutoff_xid;
+ bool all_frozen;
START_CRIT_SECTION();
@@ -1281,19 +1363,34 @@ lazy_vacuum_page(Relation onerel, BlockNumber blkno, Buffer buffer,
* dirty, exclusively locked, and, if needed, a full page image has been
* emitted in the log_heap_clean() above.
*/
- if (heap_page_is_all_visible(onerel, buffer, &visibility_cutoff_xid))
+ if (heap_page_is_all_visible(onerel, buffer, &visibility_cutoff_xid, &all_frozen))
PageSetAllVisible(page);
/*
* All the changes to the heap page have been done. If the all-visible
- * flag is now set, also set the VM bit.
+ * flag is now set, also set the VM all-visible bit.
+ * Also, if this page is all-frozen, set the VM all-frozen bit and flag.
*/
- if (PageIsAllVisible(page) &&
- !visibilitymap_test(onerel, blkno, vmbuffer))
+ if (PageIsAllVisible(page))
{
+ uint8 vm_status = visibilitymap_get_status(onerel, blkno, vmbuffer);
+ uint8 flags = 0;
+
+ if (!(vm_status & VISIBILITYMAP_ALL_VISIBLE))
+ flags |= VISIBILITYMAP_ALL_VISIBLE;
+
+ /* Set the VM all-frozen bit to flag, if needed */
+ if (all_frozen && !(vm_status & VISIBILITYMAP_ALL_FROZEN))
+ {
+ PageSetAllFrozen(page);
+ flags |= VISIBILITYMAP_ALL_FROZEN;
+ }
+
Assert(BufferIsValid(*vmbuffer));
- visibilitymap_set(onerel, blkno, buffer, InvalidXLogRecPtr, *vmbuffer,
- visibility_cutoff_xid);
+
+ if (vm_status != flags)
+ visibilitymap_set(onerel, blkno, buffer, InvalidXLogRecPtr, *vmbuffer,
+ visibility_cutoff_xid, flags);
}
return tupindex;
@@ -1783,10 +1880,12 @@ vac_cmp_itemptr(const void *left, const void *right)
/*
* Check if every tuple in the given page is visible to all current and future
* transactions. Also return the visibility_cutoff_xid which is the highest
- * xmin amongst the visible tuples.
+ * xmin amongst the visible tuples, and all_frozen which implies that all tuples
+ * of this page are frozen.
*/
static bool
-heap_page_is_all_visible(Relation rel, Buffer buf, TransactionId *visibility_cutoff_xid)
+heap_page_is_all_visible(Relation rel, Buffer buf, TransactionId *visibility_cutoff_xid,
+ bool *all_frozen)
{
Page page = BufferGetPage(buf);
BlockNumber blockno = BufferGetBlockNumber(buf);
@@ -1795,6 +1894,7 @@ heap_page_is_all_visible(Relation rel, Buffer buf, TransactionId *visibility_cut
bool all_visible = true;
*visibility_cutoff_xid = InvalidTransactionId;
+ *all_frozen = true;
/*
* This is a stripped down version of the line pointer scan in
@@ -1818,11 +1918,12 @@ heap_page_is_all_visible(Relation rel, Buffer buf, TransactionId *visibility_cut
/*
* Dead line pointers can have index pointers pointing to them. So
- * they can't be treated as visible
+ * they can't be treated as visible and frozen.
*/
if (ItemIdIsDead(itemid))
{
all_visible = false;
+ *all_frozen = false;
break;
}
@@ -1859,6 +1960,10 @@ heap_page_is_all_visible(Relation rel, Buffer buf, TransactionId *visibility_cut
/* Track newest xmin on page. */
if (TransactionIdFollows(xmin, *visibility_cutoff_xid))
*visibility_cutoff_xid = xmin;
+
+ /* Check whether this tuple is alrady frozen or not */
+ if (!HeapTupleHeaderXminFrozen(tuple.t_data))
+ *all_frozen = false;
}
break;
@@ -1867,6 +1972,7 @@ heap_page_is_all_visible(Relation rel, Buffer buf, TransactionId *visibility_cut
case HEAPTUPLE_INSERT_IN_PROGRESS:
case HEAPTUPLE_DELETE_IN_PROGRESS:
all_visible = false;
+ *all_frozen = false;
break;
default:
@@ -1875,5 +1981,8 @@ heap_page_is_all_visible(Relation rel, Buffer buf, TransactionId *visibility_cut
}
} /* scan along page */
+ if (!all_visible)
+ *all_frozen = false;
+
return all_visible;
}
diff --git a/src/backend/executor/nodeIndexonlyscan.c b/src/backend/executor/nodeIndexonlyscan.c
index 9f54c46..e345177 100644
--- a/src/backend/executor/nodeIndexonlyscan.c
+++ b/src/backend/executor/nodeIndexonlyscan.c
@@ -85,7 +85,7 @@ IndexOnlyNext(IndexOnlyScanState *node)
* which all tuples are known visible to everybody. In any case,
* we'll use the index tuple not the heap tuple as the data source.
*
- * Note on Memory Ordering Effects: visibilitymap_test does not lock
+ * Note on Memory Ordering Effects: visibilitymap_get_stattus does not lock
* the visibility map buffer, and therefore the result we read here
* could be slightly stale. However, it can't be stale enough to
* matter.
@@ -114,9 +114,8 @@ IndexOnlyNext(IndexOnlyScanState *node)
* It's worth going through this complexity to avoid needing to lock
* the VM buffer, which could cause significant contention.
*/
- if (!visibilitymap_test(scandesc->heapRelation,
- ItemPointerGetBlockNumber(tid),
- &node->ioss_VMBuffer))
+ if (!VM_ALL_VISIBLE(scandesc->heapRelation, ItemPointerGetBlockNumber(tid),
+ &node->ioss_VMBuffer))
{
/*
* Rats, we have to visit the heap to check visibility.
diff --git a/src/backend/optimizer/path/costsize.c b/src/backend/optimizer/path/costsize.c
index 990486c..d100a7d 100644
--- a/src/backend/optimizer/path/costsize.c
+++ b/src/backend/optimizer/path/costsize.c
@@ -468,7 +468,7 @@ cost_index(IndexPath *path, PlannerInfo *root, double loop_count)
* estimates based on the correlation squared (XXX is that appropriate?).
*
* If it's an index-only scan, then we will not need to fetch any heap
- * pages for which the visibility map shows all tuples are visible.
+ * pages for which the visibility map map shows all tuples are visible.
* Hence, reduce the estimated number of heap fetches accordingly.
* We use the measured fraction of the entire heap that is all-visible,
* which might not be particularly relevant to the subset of the heap
diff --git a/src/backend/postmaster/pgstat.c b/src/backend/postmaster/pgstat.c
index ab018c4..ca7257a 100644
--- a/src/backend/postmaster/pgstat.c
+++ b/src/backend/postmaster/pgstat.c
@@ -1329,7 +1329,8 @@ pgstat_report_autovac(Oid dboid)
*/
void
pgstat_report_vacuum(Oid tableoid, bool shared,
- PgStat_Counter livetuples, PgStat_Counter deadtuples)
+ PgStat_Counter livetuples, PgStat_Counter deadtuples,
+ int32 frozenpages)
{
PgStat_MsgVacuum msg;
@@ -1343,6 +1344,7 @@ pgstat_report_vacuum(Oid tableoid, bool shared,
msg.m_vacuumtime = GetCurrentTimestamp();
msg.m_live_tuples = livetuples;
msg.m_dead_tuples = deadtuples;
+ msg.m_frozen_pages = frozenpages;
pgstat_send(&msg, sizeof(msg));
}
@@ -1354,7 +1356,8 @@ pgstat_report_vacuum(Oid tableoid, bool shared,
*/
void
pgstat_report_analyze(Relation rel,
- PgStat_Counter livetuples, PgStat_Counter deadtuples)
+ PgStat_Counter livetuples, PgStat_Counter deadtuples,
+ int32 frozenpages)
{
PgStat_MsgAnalyze msg;
@@ -1394,6 +1397,7 @@ pgstat_report_analyze(Relation rel,
msg.m_analyzetime = GetCurrentTimestamp();
msg.m_live_tuples = livetuples;
msg.m_dead_tuples = deadtuples;
+ msg.m_frozen_pages = frozenpages;
pgstat_send(&msg, sizeof(msg));
}
@@ -3702,6 +3706,7 @@ pgstat_get_tab_entry(PgStat_StatDBEntry *dbentry, Oid tableoid, bool create)
result->n_live_tuples = 0;
result->n_dead_tuples = 0;
result->changes_since_analyze = 0;
+ result->n_frozen_pages = 0;
result->blocks_fetched = 0;
result->blocks_hit = 0;
result->vacuum_timestamp = 0;
@@ -5069,6 +5074,7 @@ pgstat_recv_vacuum(PgStat_MsgVacuum *msg, int len)
tabentry->n_live_tuples = msg->m_live_tuples;
tabentry->n_dead_tuples = msg->m_dead_tuples;
+ tabentry->n_frozen_pages = msg->m_frozen_pages;
if (msg->m_autovacuum)
{
@@ -5103,6 +5109,7 @@ pgstat_recv_analyze(PgStat_MsgAnalyze *msg, int len)
tabentry->n_live_tuples = msg->m_live_tuples;
tabentry->n_dead_tuples = msg->m_dead_tuples;
+ tabentry->n_frozen_pages = msg->m_frozen_pages;
/*
* We reset changes_since_analyze to zero, forgetting any changes that
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index f7c9bf6..98c14f9 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -46,6 +46,7 @@ extern Datum pg_stat_get_vacuum_count(PG_FUNCTION_ARGS);
extern Datum pg_stat_get_autovacuum_count(PG_FUNCTION_ARGS);
extern Datum pg_stat_get_analyze_count(PG_FUNCTION_ARGS);
extern Datum pg_stat_get_autoanalyze_count(PG_FUNCTION_ARGS);
+extern Datum pg_stat_get_frozen_pages(PG_FUNCTION_ARGS);
extern Datum pg_stat_get_function_calls(PG_FUNCTION_ARGS);
extern Datum pg_stat_get_function_total_time(PG_FUNCTION_ARGS);
@@ -450,6 +451,21 @@ pg_stat_get_autoanalyze_count(PG_FUNCTION_ARGS)
}
Datum
+pg_stat_get_frozen_pages(PG_FUNCTION_ARGS)
+{
+ Oid relid = PG_GETARG_OID(0);
+ int32 result;
+ PgStat_StatTabEntry *tabentry;
+
+ if ((tabentry = pgstat_fetch_stat_tabentry(relid)) == NULL)
+ result = 0;
+ else
+ result = (int32) (tabentry->n_frozen_pages);
+
+ PG_RETURN_INT32(result);
+}
+
+Datum
pg_stat_get_function_calls(PG_FUNCTION_ARGS)
{
Oid funcid = PG_GETARG_OID(0);
diff --git a/src/bin/pg_upgrade/check.c b/src/bin/pg_upgrade/check.c
index 41d4606..3a666f8 100644
--- a/src/bin/pg_upgrade/check.c
+++ b/src/bin/pg_upgrade/check.c
@@ -231,6 +231,15 @@ check_cluster_versions(void)
if (old_cluster.major_version > new_cluster.major_version)
pg_fatal("This utility cannot be used to downgrade to older major PostgreSQL versions.\n");
+ /*
+ * We can't allow upgrading with link mode between 9.5 or before and 9.6 or later,
+ * because the format of visibility map has been changed in version 9.6.
+ */
+ if (user_opts.transfer_mode == TRANSFER_MODE_LINK &&
+ GET_MAJOR_VERSION(old_cluster.major_version) < 906 &&
+ GET_MAJOR_VERSION(new_cluster.major_version) >= 906)
+ pg_fatal("This utility cannot upgrade from PostgreSQL version from 9.5 or before to 9.6 or later with link mode.\n");
+
/* get old and new binary versions */
get_bin_version(&old_cluster);
get_bin_version(&new_cluster);
diff --git a/src/bin/pg_upgrade/file.c b/src/bin/pg_upgrade/file.c
index 37eb832..d448a55 100644
--- a/src/bin/pg_upgrade/file.c
+++ b/src/bin/pg_upgrade/file.c
@@ -10,6 +10,7 @@
#include "postgres_fe.h"
#include "pg_upgrade.h"
+#include "storage/bufpage.h"
#include <fcntl.h>
@@ -21,6 +22,43 @@ static int copy_file(const char *fromfile, const char *tofile, bool force);
static int win32_pghardlink(const char *src, const char *dst);
#endif
+static const char *rewriteVisibilitymap(const char *fromfile, const char *tofile,
+ bool force);
+
+/* table for fast rewriting vm file in order to add all-frozen information */
+static const uint16 rewrite_vm_table[256] = {
+ 0, 1, 4, 5, 16, 17, 20, 21, 64, 65, 68, 69, 80, 81, 84, 85,
+ 256, 257, 260, 261, 272, 273, 276, 277, 320, 321, 324, 325, 336, 337, 340, 341,
+ 1024, 1025, 1028, 1029, 1040, 1041, 1044, 1045, 1088, 1089, 1092, 1093, 1104, 1105, 1108, 1109,
+ 1280, 1281, 1284, 1285, 1296, 1297, 1300, 1301, 1344, 1345, 1348, 1349, 1360, 1361, 1364, 1365,
+ 4096, 4097, 4100, 4101, 4112, 4113, 4116, 4117, 4160, 4161, 4164, 4165, 4176, 4177, 4180, 4181,
+ 4352, 4353, 4356, 4357, 4368, 4369, 4372, 4373, 4416, 4417, 4420, 4421, 4432, 4433, 4436, 4437,
+ 5120, 5121, 5124, 5125, 5136, 5137, 5140, 5141, 5184, 5185, 5188, 5189, 5200, 5201, 5204, 5205,
+ 5376, 5377, 5380, 5381, 5392, 5393, 5396, 5397, 5440, 5441, 5444, 5445, 5456, 5457, 5460, 5461,
+ 16384, 16385, 16388, 16389, 16400, 16401, 16404, 16405, 16448, 16449, 16452, 16453, 16464, 16465, 16468, 16469,
+ 16640, 16641, 16644, 16645, 16656, 16657, 16660, 16661, 16704, 16705, 16708, 16709, 16720, 16721, 16724, 16725,
+ 17408, 17409, 17412, 17413, 17424, 17425, 17428, 17429, 17472, 17473, 17476, 17477, 17488, 17489, 17492, 17493,
+ 17664, 17665, 17668, 17669, 17680, 17681, 17684, 17685, 17728, 17729, 17732, 17733, 17744, 17745, 17748, 17749,
+ 20480, 20481, 20484, 20485, 20496, 20497, 20500, 20501, 20544, 20545, 20548, 20549, 20560, 20561, 20564, 20565,
+ 20736, 20737, 20740, 20741, 20752, 20753, 20756, 20757, 20800, 20801, 20804, 20805, 20816, 20817, 20820, 20821,
+ 21504, 21505, 21508, 21509, 21520, 21521, 21524, 21525, 21568, 21569, 21572, 21573, 21584, 21585, 21588, 21589,
+ 21760, 21761, 21764, 21765, 21776, 21777, 21780, 21781, 21824, 21825, 21828, 21829, 21840, 21841, 21844, 21845
+};
+
+/*
+ * copyOrRewriteFile()
+ * This function copies file or rewrite visibility map file.
+ * If rewrite_vm is true, we have to rewrite visibility map regardless value of pageConverter.
+ */
+const char *
+copyOrRewriteFile(pageCnvCtx *pageConverter,
+ const char *src, const char *dst, bool force, bool rewrite_vm)
+{
+ if (rewrite_vm)
+ return rewriteVisibilitymap(src, dst, force);
+ else
+ return copyAndUpdateFile(pageConverter, src, dst, force);
+}
/*
* copyAndUpdateFile()
@@ -205,6 +243,97 @@ copy_file(const char *srcfile, const char *dstfile, bool force)
#endif
+/*
+ * rewriteVisibilitymap()
+ *
+ * A additional bit that indicates that all tuples on page is complety
+ * frozen is added into visibility map. So the format of visibility map
+ * has been changed.
+ * Copies a visibility map file while adding all-frozen bit(0) into each bit.
+ */
+static const char *
+rewriteVisibilitymap(const char *fromfile, const char *tofile, bool force)
+{
+#define REWRITE_BUF_SIZE (50 * BLCKSZ)
+#define BITS_PER_HEAPBLOCK 2
+
+ int src_fd = 0;
+ int dst_fd = 0;
+ uint16 vm_bits;
+ ssize_t nbytes;
+ char *buffer = NULL;
+ int ret = 0;
+
+ if ((fromfile == NULL) || (tofile == NULL))
+ return getErrorText(EINVAL);
+
+ if ((src_fd = open(fromfile, O_RDONLY, 0)) < 0)
+ goto err;
+
+ if ((dst_fd = open(tofile, O_RDWR | O_CREAT | (force ? 0 : O_EXCL), S_IRUSR | S_IWUSR)) < 0)
+ goto err;
+
+ buffer = (char *) pg_malloc(REWRITE_BUF_SIZE);
+
+ /* Copy page header data in advance */
+ if ((nbytes = read(src_fd, buffer, MAXALIGN(SizeOfPageHeaderData))) <= 0)
+ goto err;
+
+ if (write(dst_fd, buffer, nbytes) != nbytes)
+ {
+ /* if write didn't set errno, assume problem is no disk space */
+ if (errno == 0)
+ errno = ENOSPC;
+ goto err;
+ }
+
+ /* perform data rewriting i.e read src srouce, write to destination */
+ while (true)
+ {
+ ssize_t nbytes = read(src_fd, buffer, REWRITE_BUF_SIZE);
+ char *cur, *end;
+
+ if (nbytes < 0)
+ {
+ ret = -1;
+ break;
+ }
+
+ if (nbytes == 0)
+ break;
+
+ cur = buffer;
+ end = buffer + nbytes;
+
+ /* Rewrite a byte and write dest_fd per BITS_PER_HEAPBLOCK bytes */
+ while (end > cur)
+ {
+ /* Get rewritten bit from table and its string representation */
+ vm_bits = rewrite_vm_table[(uint8) *cur];
+
+ if (write(dst_fd, &vm_bits, BITS_PER_HEAPBLOCK) != BITS_PER_HEAPBLOCK)
+ {
+ ret = -1;
+ break;
+ }
+ cur++;
+ }
+ }
+
+err:
+
+ if (!buffer)
+ pg_free(buffer);
+
+ if (src_fd != 0)
+ close(src_fd);
+
+ if (dst_fd != 0)
+ close(dst_fd);
+
+ return (errno == 0) ? NULL : getErrorText(errno);
+}
+
void
check_hard_link(void)
{
diff --git a/src/bin/pg_upgrade/pg_upgrade.h b/src/bin/pg_upgrade/pg_upgrade.h
index fa4661b..3147480 100644
--- a/src/bin/pg_upgrade/pg_upgrade.h
+++ b/src/bin/pg_upgrade/pg_upgrade.h
@@ -110,6 +110,10 @@ extern char *output_files[];
#define VISIBILITY_MAP_CRASHSAFE_CAT_VER 201107031
/*
+ * The format of visibility map is changed with this 9.6 commit,
+ */
+#define VISIBILITY_MAP_FROZEN_BIT_CAT_VER 201511181
+/*
* pg_multixact format changed in 9.3 commit 0ac5ad5134f2769ccbaefec73844f85,
* ("Improve concurrency of foreign key locking") which also updated catalog
* version to this value. pg_upgrade behavior depends on whether old and new
@@ -394,6 +398,8 @@ const pageCnvCtx *setupPageConverter(void);
typedef void *pageCnvCtx;
#endif
+const char *copyOrRewriteFile(pageCnvCtx *pageConverter, const char *src,
+ const char *dst, bool force, bool rewrite_vm);
const char *copyAndUpdateFile(pageCnvCtx *pageConverter, const char *src,
const char *dst, bool force);
const char *linkAndUpdateFile(pageCnvCtx *pageConverter, const char *src,
diff --git a/src/bin/pg_upgrade/relfilenode.c b/src/bin/pg_upgrade/relfilenode.c
index c22df42..76418bd 100644
--- a/src/bin/pg_upgrade/relfilenode.c
+++ b/src/bin/pg_upgrade/relfilenode.c
@@ -18,7 +18,7 @@
static void transfer_single_new_db(pageCnvCtx *pageConverter,
FileNameMap *maps, int size, char *old_tablespace);
static void transfer_relfile(pageCnvCtx *pageConverter, FileNameMap *map,
- const char *suffix);
+ const char *suffix, bool vm_need_rewrite);
/*
@@ -171,6 +171,7 @@ transfer_single_new_db(pageCnvCtx *pageConverter,
{
int mapnum;
bool vm_crashsafe_match = true;
+ bool vm_need_rewrite = false;
/*
* Do the old and new cluster disagree on the crash-safetiness of the vm
@@ -180,13 +181,20 @@ transfer_single_new_db(pageCnvCtx *pageConverter,
new_cluster.controldata.cat_ver >= VISIBILITY_MAP_CRASHSAFE_CAT_VER)
vm_crashsafe_match = false;
+ /*
+ * Do we need to rewrite visibilitymap?
+ */
+ if (old_cluster.controldata.cat_ver < VISIBILITY_MAP_FROZEN_BIT_CAT_VER &&
+ new_cluster.controldata.cat_ver >= VISIBILITY_MAP_FROZEN_BIT_CAT_VER)
+ vm_need_rewrite = true;
+
for (mapnum = 0; mapnum < size; mapnum++)
{
if (old_tablespace == NULL ||
strcmp(maps[mapnum].old_tablespace, old_tablespace) == 0)
{
/* transfer primary file */
- transfer_relfile(pageConverter, &maps[mapnum], "");
+ transfer_relfile(pageConverter, &maps[mapnum], "", false);
/* fsm/vm files added in PG 8.4 */
if (GET_MAJOR_VERSION(old_cluster.major_version) >= 804)
@@ -194,9 +202,14 @@ transfer_single_new_db(pageCnvCtx *pageConverter,
/*
* Copy/link any fsm and vm files, if they exist
*/
- transfer_relfile(pageConverter, &maps[mapnum], "_fsm");
+ transfer_relfile(pageConverter, &maps[mapnum], "_fsm", false);
if (vm_crashsafe_match)
- transfer_relfile(pageConverter, &maps[mapnum], "_vm");
+ {
+ if (vm_need_rewrite)
+ transfer_relfile(pageConverter, &maps[mapnum], "_vm", true);
+ else
+ transfer_relfile(pageConverter, &maps[mapnum], "_vm", false);
+ }
}
}
}
@@ -210,7 +223,7 @@ transfer_single_new_db(pageCnvCtx *pageConverter,
*/
static void
transfer_relfile(pageCnvCtx *pageConverter, FileNameMap *map,
- const char *type_suffix)
+ const char *type_suffix, bool vm_need_rewrite)
{
const char *msg;
char old_file[MAXPGPATH];
@@ -276,7 +289,7 @@ transfer_relfile(pageCnvCtx *pageConverter, FileNameMap *map,
{
pg_log(PG_VERBOSE, "copying \"%s\" to \"%s\"\n", old_file, new_file);
- if ((msg = copyAndUpdateFile(pageConverter, old_file, new_file, true)) != NULL)
+ if ((msg = copyOrRewriteFile(pageConverter, old_file, new_file, true, vm_need_rewrite)) != NULL)
pg_fatal("error while copying relation \"%s.%s\" (\"%s\" to \"%s\"): %s\n",
map->nspname, map->relname, old_file, new_file, msg);
}
diff --git a/src/bin/pg_upgrade/test.sh b/src/bin/pg_upgrade/test.sh
index aa7f399..6b058d4 100644
--- a/src/bin/pg_upgrade/test.sh
+++ b/src/bin/pg_upgrade/test.sh
@@ -174,6 +174,11 @@ if "$MAKE" -C "$oldsrc" installcheck; then
mv "$temp_root"/dump1.sql "$temp_root"/dump1.sql.orig
sed "s;$oldsrc;$newsrc;g" "$temp_root"/dump1.sql.orig >"$temp_root"/dump1.sql
fi
+
+ vm_sql="SELECT c.relname, c.relallvisible FROM pg_class as c, pg_namespace as n WHERE c.relnamespace = n.oid AND n.nspname NOT IN ('information_schema', 'pg_toast', 'pg_catalog') ORDER BY c.relname;"
+ # Test for rewriting visibility map
+ vacuumdb -d regression || visibilitymap_vacuum1_status=$?
+ psql -d regression -c "$vm_sql" > "$temp_root"/vm_test1.txt || visibilitymap_test1_status=$?
else
make_installcheck_status=$?
fi
@@ -188,6 +193,14 @@ if [ -n "$pg_dumpall1_status" ]; then
echo "pg_dumpall of pre-upgrade database cluster failed"
exit 1
fi
+if [ -n "$visibilitymap_vacuum1_status" ];then
+ echo "VACUUM of pre-upgrade database cluster for visibility map test failed"
+ exit 1
+fi
+if [ -n "$visibilitymap_test1_status" ];then
+ echo "SELECT of pre-upgrade database cluster for visibility map test failed"
+ exit 1
+fi
PGDATA=$BASE_PGDATA
@@ -203,6 +216,8 @@ case $testhost in
esac
pg_dumpall -f "$temp_root"/dump2.sql || pg_dumpall2_status=$?
+vacuumdb -d regression || visibilitymap_vacuum2_status=$?
+psql -d regression -c "$vm_sql" > "$temp_root"/vm_test2.txt || visibilitymap_test2_status=$?
pg_ctl -m fast stop
# no need to echo commands anymore
@@ -214,11 +229,26 @@ if [ -n "$pg_dumpall2_status" ]; then
exit 1
fi
+if [ -n "$visibilitymap_vacuum2_status" ];then
+ echo "VACUUM of post-upgrade database cluster for visibility map test failed"
+ exit 1
+fi
+
+if [ -n "$visibilitymap_test2_status" ];then
+ echo "SELECT of post-upgrade database cluster for visibility map test failed"
+ exit 1
+fi
+
case $testhost in
MINGW*) cmd /c delete_old_cluster.bat ;;
*) sh ./delete_old_cluster.sh ;;
esac
+if ! diff "$temp_root"/vm_test1.txt "$temp_root"/vm_test2.txt >/dev/null; then
+ echo "Visibility map rewriting test failed"
+ exit 1
+fi
+
if diff "$temp_root"/dump1.sql "$temp_root"/dump2.sql >/dev/null; then
echo PASSED
exit 0
diff --git a/src/include/access/heapam_xlog.h b/src/include/access/heapam_xlog.h
index caa0f14..c55d232 100644
--- a/src/include/access/heapam_xlog.h
+++ b/src/include/access/heapam_xlog.h
@@ -320,9 +320,10 @@ typedef struct xl_heap_freeze_page
typedef struct xl_heap_visible
{
TransactionId cutoff_xid;
+ uint8 flags;
} xl_heap_visible;
-#define SizeOfHeapVisible (offsetof(xl_heap_visible, cutoff_xid) + sizeof(TransactionId))
+#define SizeOfHeapVisible (offsetof(xl_heap_visible, flags) + sizeof(uint8))
typedef struct xl_heap_new_cid
{
@@ -389,6 +390,6 @@ extern bool heap_prepare_freeze_tuple(HeapTupleHeader tuple,
extern void heap_execute_freeze_tuple(HeapTupleHeader tuple,
xl_heap_freeze_tuple *xlrec_tp);
extern XLogRecPtr log_heap_visible(RelFileNode rnode, Buffer heap_buffer,
- Buffer vm_buffer, TransactionId cutoff_xid);
+ Buffer pim_buffer, TransactionId cutoff_xid, uint8 flags);
#endif /* HEAPAM_XLOG_H */
diff --git a/src/include/access/hio.h b/src/include/access/hio.h
index b3b91e7..a200e5e 100644
--- a/src/include/access/hio.h
+++ b/src/include/access/hio.h
@@ -40,6 +40,6 @@ extern void RelationPutHeapTuple(Relation relation, Buffer buffer,
extern Buffer RelationGetBufferForTuple(Relation relation, Size len,
Buffer otherBuffer, int options,
BulkInsertState bistate,
- Buffer *vmbuffer, Buffer *vmbuffer_other);
+ Buffer *pimbuffer, Buffer *pimbuffer_other);
#endif /* HIO_H */
diff --git a/src/include/access/visibilitymap.h b/src/include/access/visibilitymap.h
index 0c0e0ef..5f032ab 100644
--- a/src/include/access/visibilitymap.h
+++ b/src/include/access/visibilitymap.h
@@ -19,15 +19,28 @@
#include "storage/buf.h"
#include "utils/relcache.h"
+/* Flags for bit map */
+#define VISIBILITYMAP_ALL_VISIBLE 0x01
+#define VISIBILITYMAP_ALL_FROZEN 0x02
+
+#define VISIBILITYMAP_VALID_BITS 0x03 /* OR of all valid visiblitymap flags bits */
+
+/* Macros for visibilitymap test */
+#define VM_ALL_VISIBLE(r, b, v) \
+ ((visibilitymap_get_status((r), (b), (v)) & VISIBILITYMAP_ALL_VISIBLE) != 0)
+#define VM_ALL_FROZEN(r, b, v) \
+ ((visibilitymap_get_status((r), (b), (v)) & VISIBILITYMAP_ALL_FROZEN) != 0)
+
extern void visibilitymap_clear(Relation rel, BlockNumber heapBlk,
Buffer vmbuf);
extern void visibilitymap_pin(Relation rel, BlockNumber heapBlk,
Buffer *vmbuf);
extern bool visibilitymap_pin_ok(BlockNumber heapBlk, Buffer vmbuf);
extern void visibilitymap_set(Relation rel, BlockNumber heapBlk, Buffer heapBuf,
- XLogRecPtr recptr, Buffer vmBuf, TransactionId cutoff_xid);
-extern bool visibilitymap_test(Relation rel, BlockNumber heapBlk, Buffer *vmbuf);
-extern BlockNumber visibilitymap_count(Relation rel);
+ XLogRecPtr recptr, Buffer vmBuf, TransactionId cutoff_xid,
+ uint8 flags);
+extern uint8 visibilitymap_get_status(Relation rel, BlockNumber heapBlk, Buffer *vmbuf);
+extern BlockNumber visibilitymap_count(Relation rel, BlockNumber *all_frozen);
extern void visibilitymap_truncate(Relation rel, BlockNumber nheapblocks);
#endif /* VISIBILITYMAP_H */
diff --git a/src/include/catalog/catversion.h b/src/include/catalog/catversion.h
index eba4150..f6ae108 100644
--- a/src/include/catalog/catversion.h
+++ b/src/include/catalog/catversion.h
@@ -53,6 +53,6 @@
*/
/* yyyymmddN */
-#define CATALOG_VERSION_NO 201511071
+#define CATALOG_VERSION_NO 201511181
#endif
diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h
index d8640db..9a77d7d 100644
--- a/src/include/catalog/pg_proc.h
+++ b/src/include/catalog/pg_proc.h
@@ -2779,6 +2779,8 @@ DATA(insert OID = 3056 ( pg_stat_get_analyze_count PGNSP PGUID 12 1 0 0 0 f f f
DESCR("statistics: number of manual analyzes for a table");
DATA(insert OID = 3057 ( pg_stat_get_autoanalyze_count PGNSP PGUID 12 1 0 0 0 f f f f t f s r 1 0 20 "26" _null_ _null_ _null_ _null_ _null_ pg_stat_get_autoanalyze_count _null_ _null_ _null_ ));
DESCR("statistics: number of auto analyzes for a table");
+DATA(insert OID = 6015 ( pg_stat_get_frozen_pages PGNSP PGUID 12 1 0 0 0 f f f f t f s r 1 0 23 "26" _null_ _null_ _null_ _null_ _null_ pg_stat_get_frozen_pages _null_ _null_ _null_ ));
+DESCR("statistics: number of frozen pages of table");
DATA(insert OID = 1936 ( pg_stat_get_backend_idset PGNSP PGUID 12 1 100 0 0 f f f f t t s r 0 0 23 "" _null_ _null_ _null_ _null_ _null_ pg_stat_get_backend_idset _null_ _null_ _null_ ));
DESCR("statistics: currently active backend IDs");
DATA(insert OID = 2022 ( pg_stat_get_activity PGNSP PGUID 12 1 100 0 0 f f f f f t s r 1 0 2249 "23" "{23,26,23,26,25,25,25,16,1184,1184,1184,1184,869,25,23,28,28,16,25,25,23,16,25}" "{i,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}" "{pid,datid,pid,usesysid,application_name,state,query,waiting,xact_start,query_start,backend_start,state_change,client_addr,client_hostname,client_port,backend_xid,backend_xmin,ssl,sslversion,sslcipher,sslbits,sslcompression,sslclientdn}" _null_ _null_ pg_stat_get_activity _null_ _null_ _null_ ));
diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h
index eb3591a..6165500 100644
--- a/src/include/nodes/execnodes.h
+++ b/src/include/nodes/execnodes.h
@@ -1363,7 +1363,7 @@ typedef struct IndexScanState
* RuntimeContext expr context for evaling runtime Skeys
* RelationDesc index relation descriptor
* ScanDesc index scan descriptor
- * VMBuffer buffer in use for visibility map testing, if any
+ * PIMBuffer buffer in use for visibility map testing, if any
* HeapFetches number of tuples we were forced to fetch from heap
* ----------------
*/
diff --git a/src/include/pgstat.h b/src/include/pgstat.h
index 9ecc163..614ca5a 100644
--- a/src/include/pgstat.h
+++ b/src/include/pgstat.h
@@ -355,6 +355,7 @@ typedef struct PgStat_MsgVacuum
TimestampTz m_vacuumtime;
PgStat_Counter m_live_tuples;
PgStat_Counter m_dead_tuples;
+ int32 m_frozen_pages;
} PgStat_MsgVacuum;
@@ -372,6 +373,7 @@ typedef struct PgStat_MsgAnalyze
TimestampTz m_analyzetime;
PgStat_Counter m_live_tuples;
PgStat_Counter m_dead_tuples;
+ int32 m_frozen_pages;
} PgStat_MsgAnalyze;
@@ -551,7 +553,7 @@ typedef union PgStat_Msg
* ------------------------------------------------------------
*/
-#define PGSTAT_FILE_FORMAT_ID 0x01A5BC9D
+#define PGSTAT_FILE_FORMAT_ID 0x01A5BC9E
/* ----------
* PgStat_StatDBEntry The collector's data per database
@@ -615,6 +617,8 @@ typedef struct PgStat_StatTabEntry
PgStat_Counter n_dead_tuples;
PgStat_Counter changes_since_analyze;
+ int32 n_frozen_pages;
+
PgStat_Counter blocks_fetched;
PgStat_Counter blocks_hit;
@@ -917,9 +921,11 @@ extern void pgstat_reset_single_counter(Oid objectid, PgStat_Single_Reset_Type t
extern void pgstat_report_autovac(Oid dboid);
extern void pgstat_report_vacuum(Oid tableoid, bool shared,
- PgStat_Counter livetuples, PgStat_Counter deadtuples);
+ PgStat_Counter livetuples, PgStat_Counter deadtuples,
+ int32 frozenpages);
extern void pgstat_report_analyze(Relation rel,
- PgStat_Counter livetuples, PgStat_Counter deadtuples);
+ PgStat_Counter livetuples, PgStat_Counter deadtuples,
+ int32 frozenpages);
extern void pgstat_report_recovery_conflict(int reason);
extern void pgstat_report_deadlock(void);
diff --git a/src/include/storage/bufpage.h b/src/include/storage/bufpage.h
index a2f78ee..102aa81 100644
--- a/src/include/storage/bufpage.h
+++ b/src/include/storage/bufpage.h
@@ -178,8 +178,10 @@ typedef PageHeaderData *PageHeader;
* tuple? */
#define PD_ALL_VISIBLE 0x0004 /* all tuples on page are visible to
* everyone */
+#define PD_ALL_FROZEN 0x0008 /* all tuples on page are completely
+ frozen */
-#define PD_VALID_FLAG_BITS 0x0007 /* OR of all valid pd_flags bits */
+#define PD_VALID_FLAG_BITS 0x000F /* OR of all valid pd_flags bits */
/*
* Page layout version number 0 is for pre-7.3 Postgres releases.
@@ -367,7 +369,12 @@ typedef PageHeaderData *PageHeader;
#define PageSetAllVisible(page) \
(((PageHeader) (page))->pd_flags |= PD_ALL_VISIBLE)
#define PageClearAllVisible(page) \
- (((PageHeader) (page))->pd_flags &= ~PD_ALL_VISIBLE)
+ (((PageHeader) (page))->pd_flags &= ~(PD_ALL_VISIBLE | PD_ALL_FROZEN))
+
+#define PageIsAllFrozen(page) \
+ (((PageHeader) (page))->pd_flags & PD_ALL_FROZEN)
+#define PageSetAllFrozen(page) \
+ (((PageHeader) (page))->pd_flags |= PD_ALL_FROZEN)
#define PageIsPrunable(page, oldestxmin) \
( \
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index 80374e4..b259e65 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -1683,6 +1683,7 @@ pg_stat_all_tables| SELECT c.oid AS relid,
pg_stat_get_live_tuples(c.oid) AS n_live_tup,
pg_stat_get_dead_tuples(c.oid) AS n_dead_tup,
pg_stat_get_mod_since_analyze(c.oid) AS n_mod_since_analyze,
+ pg_stat_get_frozen_pages(c.oid) AS n_frozen_page,
pg_stat_get_last_vacuum_time(c.oid) AS last_vacuum,
pg_stat_get_last_autovacuum_time(c.oid) AS last_autovacuum,
pg_stat_get_last_analyze_time(c.oid) AS last_analyze,
@@ -1795,6 +1796,7 @@ pg_stat_sys_tables| SELECT pg_stat_all_tables.relid,
pg_stat_all_tables.n_live_tup,
pg_stat_all_tables.n_dead_tup,
pg_stat_all_tables.n_mod_since_analyze,
+ pg_stat_all_tables.n_frozen_page,
pg_stat_all_tables.last_vacuum,
pg_stat_all_tables.last_autovacuum,
pg_stat_all_tables.last_analyze,
@@ -1838,6 +1840,7 @@ pg_stat_user_tables| SELECT pg_stat_all_tables.relid,
pg_stat_all_tables.n_live_tup,
pg_stat_all_tables.n_dead_tup,
pg_stat_all_tables.n_mod_since_analyze,
+ pg_stat_all_tables.n_frozen_page,
pg_stat_all_tables.last_vacuum,
pg_stat_all_tables.last_autovacuum,
pg_stat_all_tables.last_analyze,
diff --git a/src/test/regress/expected/stats.out b/src/test/regress/expected/stats.out
index f5be70f..dd49786 100644
--- a/src/test/regress/expected/stats.out
+++ b/src/test/regress/expected/stats.out
@@ -127,6 +127,8 @@ SELECT count(*) FROM tenk2 WHERE unique1 = 1;
1
(1 row)
+-- do VACUUM FREEZE
+VACUUM FREEZE tenk2;
-- force the rate-limiting logic in pgstat_report_tabstat() to time out
-- and send a message
SELECT pg_sleep(1.0);
@@ -175,6 +177,14 @@ SELECT st.heap_blks_read + st.heap_blks_hit >= pr.heap_blks + cl.relpages,
t | t
(1 row)
+SELECT n_frozen_page = (pg_relation_size('tenk2') / current_setting('block_size')::int)
+ FROM pg_stat_user_tables
+ WHERE relname ='tenk2';
+ ?column?
+----------
+ t
+(1 row)
+
SELECT pr.snap_ts < pg_stat_get_snapshot_timestamp() as snapshot_newer
FROM prevstats AS pr;
snapshot_newer
diff --git a/src/test/regress/expected/visibilitymap.out b/src/test/regress/expected/visibilitymap.out
new file mode 100644
index 0000000..3be0354
--- /dev/null
+++ b/src/test/regress/expected/visibilitymap.out
@@ -0,0 +1,22 @@
+--
+-- Visibility Map
+--
+CREATE TABLE vmtest (i INT primary key);
+INSERT INTO vmtest SELECT generate_series(1,10000);
+-- All pages are become all-visible
+VACUUM FREEZE vmtest;
+SELECT relallvisible = (pg_relation_size('vmtest') / current_setting('block_size')::int) FROM pg_class WHERE relname = 'vmtest';
+ ?column?
+----------
+ t
+(1 row)
+
+-- Check whether vacuum skips all-frozen pages
+\set VERBOSITY terse
+VACUUM FREEZE VERBOSE vmtest;
+INFO: vacuuming "public.vmtest"
+INFO: index "vmtest_pkey" now contains 10000 row versions in 30 pages
+INFO: skipped 45 frozen pages according to visibility map
+INFO: "vmtest": found 0 removable, 0 nonremovable row versions in 0 out of 45 pages
+\set VERBOSITY default
+DROP TABLE vmtest;
diff --git a/src/test/regress/parallel_schedule b/src/test/regress/parallel_schedule
index 3987b4c..5253a29 100644
--- a/src/test/regress/parallel_schedule
+++ b/src/test/regress/parallel_schedule
@@ -110,3 +110,6 @@ test: event_trigger
# run stats by itself because its delay may be insufficient under heavy load
test: stats
+
+# page info map and vacuum test cannot run concurrently with any test that runs SQL
+test: visibilitymap
diff --git a/src/test/regress/serial_schedule b/src/test/regress/serial_schedule
index 379f272..c5fd695 100644
--- a/src/test/regress/serial_schedule
+++ b/src/test/regress/serial_schedule
@@ -160,3 +160,4 @@ test: with
test: xml
test: event_trigger
test: stats
+test: visibilitymap
diff --git a/src/test/regress/sql/stats.sql b/src/test/regress/sql/stats.sql
index cd2d592..b3c640f 100644
--- a/src/test/regress/sql/stats.sql
+++ b/src/test/regress/sql/stats.sql
@@ -120,6 +120,8 @@ ROLLBACK;
SELECT count(*) FROM tenk2;
-- do an indexscan
SELECT count(*) FROM tenk2 WHERE unique1 = 1;
+-- do VACUUM FREEZE
+VACUUM FREEZE tenk2;
-- force the rate-limiting logic in pgstat_report_tabstat() to time out
-- and send a message
@@ -145,6 +147,10 @@ SELECT st.heap_blks_read + st.heap_blks_hit >= pr.heap_blks + cl.relpages,
FROM pg_statio_user_tables AS st, pg_class AS cl, prevstats AS pr
WHERE st.relname='tenk2' AND cl.relname='tenk2';
+SELECT n_frozen_page = (pg_relation_size('tenk2') / current_setting('block_size')::int)
+ FROM pg_stat_user_tables
+ WHERE relname ='tenk2';
+
SELECT pr.snap_ts < pg_stat_get_snapshot_timestamp() as snapshot_newer
FROM prevstats AS pr;
diff --git a/src/test/regress/sql/visibilitymap.sql b/src/test/regress/sql/visibilitymap.sql
new file mode 100644
index 0000000..365570b
--- /dev/null
+++ b/src/test/regress/sql/visibilitymap.sql
@@ -0,0 +1,16 @@
+--
+-- Visibility Map
+--
+CREATE TABLE vmtest (i INT primary key);
+INSERT INTO vmtest SELECT generate_series(1,10000);
+
+-- All pages are become all-visible
+VACUUM FREEZE vmtest;
+SELECT relallvisible = (pg_relation_size('vmtest') / current_setting('block_size')::int) FROM pg_class WHERE relname = 'vmtest';
+
+-- Check whether vacuum skips all-frozen pages
+\set VERBOSITY terse
+VACUUM FREEZE VERBOSE vmtest;
+\set VERBOSITY default
+
+DROP TABLE vmtest;
--
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