permitted.
If idea is accepted, patches for tests will be applied as well.
[1]
https://git.postgresql.org/gitweb/?p=postgresql.git;a=patch;h=c945af80
---
Yura Sokolov.From 173cfc3762a97c300b618f863fd23433909cdb81 Mon Sep 17 00:00:00 2001
From: Yura Sokolov
Date: Wed, 3 May 2023 18:48:46 +03
06.09.2023 13:24, Yura Sokolov wrote:
24.08.2023 17:07, Maxim Orlov wrote:
Hi!
Recently, I've been playing around with pg_lists and realize how
annoying (maybe, I was a bit tired) some stuff related to the lists.
For an example, see this code
List *l1 = list_make4(1, 2, 3, 4
24.08.2023 17:07, Maxim Orlov wrote:
Hi!
Recently, I've been playing around with pg_lists and realize how
annoying (maybe, I was a bit tired) some stuff related to the lists.
For an example, see this code
List *l1 = list_make4(1, 2, 3, 4),
*l2 = list_make4(5, 6, 7, 8),
15.06.2023 17:49, Tom Lane пишет:
"David G. Johnston" writes:
The failure to find and execute the function code itself is not a failure
mode that these markers need be concerned with. Assuming one can execute
the function an immutable function will give the same answer for the same
input
15.06.2023 16:58, c...@anastigmatix.net пишет:
On 2023-06-15 09:21, Tom Lane wrote:
Yura Sokolov writes:
not enough to be sure function doesn't manipulate data.
Of course not. It is the user's responsibility to mark functions
properly.
And also, isn't it the case that IMMUTABLE should
15.06.2023 16:21, Tom Lane wrote:
Yura Sokolov writes:
I found, than declaration of function as IMMUTABLE/STABLE is not enough to be
sure
function doesn't manipulate data.
Of course not. It is the user's responsibility to mark functions
properly. Trying to enforce that completely
of ERROR. And ERROR should be generated at same place, when
it is generated for `immutable_direct`, but with check of "read_only"
status through
whole call stack instead of just direct function kind.
-
regards,
Yura Sokolov
Postgres Professional
when it is generated for
`immutable_direct`, but with check of "read_only" status through whole
call stack instead of just direct function kind. - regards, Yura
Sokolov Postgres Professional
immutable_not.sql
Description: application/sql
diff --git a/src/backend/executor/spi.c b/sr
_var
(*(my_hello_var_t*)(CurSessionVar(my_hello_var_offset)))
/* module.c */
size_t my_hello_var_offset = 0;
void
PG_init() {
RegisterSessionVar(sizeof(my_hello_var_t), _hello_var_offset);
}
For security reasons, offset could be mangled.
--
regards,
Yura Sokolov
usage in token success or error reporting,
- simplify json_lex_number and its usage a bit.
Also he added tests for fixed bug.
-
Regards,
Yura Sokolov.
From 757a314d5fa9c6ba8334762b4a080763f02244c5 Mon Sep 17 00:00:00 2001
From: Nikita Glukhov
Date: Tue, 14 Mar 2023 12:15:48 +0300
Subject: [PATCH]
В Ср, 07/09/2022 в 16:13 +1200, David Rowley пишет:
> On Tue, 6 Sept 2022 at 01:41, David Rowley wrote:
> >
> > On Fri, 2 Sept 2022 at 20:11, David Rowley wrote:
> > >
> > > On Thu, 1 Sept 2022 at 12:46, Tom Lane wrote:
> > > >
> > > > David Rowley writes:
> > > > > Maybe we should just
h-valgrind --without-pymalloc`
Valgrind doesn't complain, so there are no memory related
issues in plpython.
regards
------
Yura Sokolov
y.sokolov
diff --git a/src/pl/plpython/plpy_elog.c b/src/pl/plpython/plpy_elog.c
index 7c627eacfbf..aa1cf17b366 100644
--- a/src/pl/plpython/plpy_elog.c
+++ b/src/p
5960b8af917e9268881cd8df3f88320%40postgrespro.ru
> [1] https://postgr.es/m/057a9a95-19d2-05f0-17e2-f46ff20e9b3e%402ndquadrant.com
>
I'm glad my idea has been reborn.
Well, may be simplehash is not bad idea.
While it certainly consumes more memory and CPU instructions.
I'll try to review.
regards,
Yura Sokolov
Good day, Thomas
В Пт, 27/05/2022 в 23:24 +1200, Thomas Munro пишет:
> Rebased, debugged and fleshed out a tiny bit more, but still with
> plenty of TODO notes and questions. I will talk about this idea at
> PGCon, so I figured it'd help to have a patch that actually applies,
> even if it
of patch diff.
Rebased versions of first two patch parts are attached.
regards,
Yura Sokolov
slru-ballast.sql
Description: application/sql
slru-call.sql
Description: application/sql
slru-func.sql
Description: application/sql
From 41ec9d1c54184c515d53ecc8021c4a998813f2a9 Mon Sep 17 00:00:00 2001
В Вт, 12/07/2022 в 22:41 -0700, Andres Freund пишет:
> Hi,
>
> On 2022-07-12 10:42:07 -0700, Andres Freund wrote:
> > On 2022-07-12 17:01:18 +1200, David Rowley wrote:
> > > There is at least one. It might be major; to reduce the AllocSet chunk
> > > header from 16 bytes down to 8 bytes I had to
Good day, David.
В Вт, 12/07/2022 в 17:01 +1200, David Rowley пишет:
> Over on [1], I highlighted that 40af10b57 (Use Generation memory
> contexts to store tuples in sorts) could cause some performance
> regressions for sorts when the size of the tuple is exactly a power of
> 2. The reason for
В Сб, 09/07/2022 в 02:32 +0300, Yura Sokolov пишет:
> В Пт, 08/07/2022 в 11:04 -0400, Robert Haas пишет:
> > On Fri, Jul 8, 2022 at 10:11 AM Yura Sokolov
> > wrote:
> > > I see analogy with Bus Stop:
> > > - there is bus stop
> > > - th
В Пт, 08/07/2022 в 11:04 -0400, Robert Haas пишет:
> On Fri, Jul 8, 2022 at 10:11 AM Yura Sokolov wrote:
> > I see analogy with Bus Stop:
> > - there is bus stop
> > - there is a schedule of bus arriving this top
> > - there are passengers, who every day travel
В Пт, 08/07/2022 в 09:44 -0400, Robert Haas пишет:
> On Thu, Jul 7, 2022 at 10:39 PM Kyotaro Horiguchi
> wrote:
> > At Thu, 7 Jul 2022 13:58:06 -0500, Justin Pryzby
> > wrote in
> > > I agree that this is a bug, since it can (and did) cause false positives
> > > in a
> > > monitoring system.
>
В Вт, 28/06/2022 в 14:26 +0300, Yura Sokolov пишет:
> В Вт, 28/06/2022 в 14:13 +0300, Yura Sokolov пишет:
>
> > Tests:
> > - tests done on 2 socket Xeon 5220 2.20GHz with turbo bust disabled
> > (ie max frequency is 2.20GHz)
>
> Forgot to mention:
> - this
В Вт, 28/06/2022 в 14:13 +0300, Yura Sokolov пишет:
> Tests:
> - tests done on 2 socket Xeon 5220 2.20GHz with turbo bust disabled
> (ie max frequency is 2.20GHz)
Forgot to mention:
- this time it was Centos7.9.2009 (Core) with Linux mn10 3.10.0-1160.el7.x86_64
Perhaps older kernel
Fr, 27/05/2022 в 10:51 -0400, Tom Lane writes:
> Yura Sokolov writes:
> > В Вт, 24/05/2022 в 17:39 -0700, Andres Freund пишет:
> > > A variation on your patch would be to only store the offset to the block
> > > header - that should always fit into 32bit (huge allocat
be encoded in
chunk-body itself instead of header. I was confused with this, since
there are valgrind hooks, and I was not sure how to change it (I'm
not good at valgrind hooks). But after thinking more about I believe
it is doable.
regards
---
Yura Sokolov
В Пт, 06/05/2022 в 10:26 -0400, Robert Haas пишет:
> On Thu, Apr 21, 2022 at 6:58 PM Yura Sokolov wrote:
> > At the master state:
> > - SharedBufHash is not declared as HASH_FIXED_SIZE
> > - get_hash_entry falls back to element_alloc too fast (just if it doesn't
> >
В Чт, 28/04/2022 в 17:37 +0530, vignesh C пишет:
> On Thu, Apr 28, 2022 at 4:24 PM Yura Sokolov wrote:
> > В Чт, 28/04/2022 в 09:49 +1000, Peter Smith пишет:
> >
> > > 1.1 ADVANTAGES OF MMLR
> > >
> > > - Increases write scalability (e.g., all node
ration of MM. First iteration were
not "simple" or "easy" already. But even that version had
the hidden bug: rare but accumulating data difference
between nodes. Attempt to fix this bug led to almost
full rewrite of multi-master.
(Disclaimer: I had no relation to both MM versions,
I just work in the same firm).
regards
-
Yura Sokolov
Btw, I've runned tests on EPYC (80 cores).
1 key per select
conns | master | patch-v11 | master 1G | patch-v11 1G
++++
1 | 29053 | 28959 | 26715 | 25631
2 | 53714 | 53002 | 55211 |
В Чт, 21/04/2022 в 16:24 -0400, Robert Haas пишет:
> On Thu, Apr 21, 2022 at 5:04 AM Yura Sokolov wrote:
> > $ pid=`ps x | awk '/checkpointer/ && !/awk/ { print $1 }'`
> > $ gdb -p $pid -batch -ex 'p SharedBufHash->hctl->allocated.value'
> >
> > $1
e is "out of shared memory" which is avoidable with get_hash_entry
modifications or with HASH_FIXED_SIZE + some spare items.
Could CHECK_FOR_INTERRUPTS raise something?
No: there is single line between LWLockRelease and LWLockAcquire, and
it doesn't contain CHECK_FOR_INTERRUPTS.
Therefore there is single fixable case of "out of shared memory" (by
HASH_FIXED_SIZE or improvements to "get_hash_entry").
May be I'm not quite right at some point. I'd glad to learn.
-
regards
Yura Sokolov
В Пт, 08/04/2022 в 16:46 +0900, Kyotaro Horiguchi пишет:
> At Thu, 07 Apr 2022 14:14:59 +0300, Yura Sokolov
> wrote in
> > В Чт, 07/04/2022 в 16:55 +0900, Kyotaro Horiguchi пишет:
> > > Hi, Yura.
> > >
> > > At Wed, 06 Apr 2022 16:17:28 +0300, Yura Soko
В Чт, 07/04/2022 в 16:55 +0900, Kyotaro Horiguchi пишет:
> Hi, Yura.
>
> At Wed, 06 Apr 2022 16:17:28 +0300, Yura Sokolov
> wrot
> e in
> > Ok, I got access to stronger server, did the benchmark, found weird
> > things, and so here is new version :-)
>
Good day, Kyotaoro-san.
Good day, hackers.
В Вс, 20/03/2022 в 12:38 +0300, Yura Sokolov пишет:
> В Чт, 17/03/2022 в 12:02 +0900, Kyotaro Horiguchi пишет:
> > At Wed, 16 Mar 2022 14:11:58 +0300, Yura Sokolov
> > wrote in
> > > В Ср, 16/03/2022 в 12:07 +0900,
source owners usually form stack, so usually
when owner searches for itself it is last added to list.
Then `dlist_foreach` will find it sooner if it were added to the head.
regards
-
Yura Sokolov
Postgres Professional
y.soko...@postgrespro.ru
funny.fal...@gmail.com
Good day.
v14 introduced the way to get original text for some kind of expressions
using new 'funcformat' - COERCE_SQL_SYNTAX:
- EXTRACT(part from timestamp)
- (text IS [form] NORMALIZED)
and others.
Mentioned EXTRACT and NORMALIZED statements has parts, that are not
usual arguments but some
В Чт, 17/03/2022 в 12:02 +0900, Kyotaro Horiguchi пишет:
> At Wed, 16 Mar 2022 14:11:58 +0300, Yura Sokolov
> wrote in
> > В Ср, 16/03/2022 в 12:07 +0900, Kyotaro Horiguchi пишет:
> > > At Tue, 15 Mar 2022 13:47:17 +0300, Yura Sokolov
> > > wrote in
&
PG_HAVE_8BYTE_SINGLE_COPY_ATOMICITY
for aarch64
[1] https://documentation-service.arm.com/static/61fbe8f4fa8173727a1b734e
https://developer.arm.com/documentation/ddi0487/latest
---
regards
Yura Sokolov
Postgres Professional
y.soko...@postgrespro.ru
funny.fal...@gmail.com
From
В Ср, 16/03/2022 в 12:07 +0900, Kyotaro Horiguchi пишет:
> At Tue, 15 Mar 2022 13:47:17 +0300, Yura Sokolov
> wrote in
> > В Вт, 15/03/2022 в 16:25 +0900, Kyotaro Horiguchi пишет:
> > > Hmm. v8 returns stashed element with original patition index when the
> >
В Вт, 15/03/2022 в 13:47 +0300, Yura Sokolov пишет:
> В Вт, 15/03/2022 в 16:25 +0900, Kyotaro Horiguchi пишет:
> > Thanks for the new version.
> >
> > At Tue, 15 Mar 2022 08:07:39 +0300, Yura Sokolov
> > wrote in
> > > В Пн, 14/03/2022 в 14:57 +0300, Yur
В Вт, 15/03/2022 в 13:47 +0300, Yura Sokolov пишет:
> В Вт, 15/03/2022 в 16:25 +0900, Kyotaro Horiguchi пишет:
> > > I lost access to Xeon 8354H, so returned to old Xeon X5675.
> > ...
> > > Strange thing: both master and patched version has higher
> > > peak tp
В Вт, 15/03/2022 в 16:25 +0900, Kyotaro Horiguchi пишет:
> Thanks for the new version.
>
> At Tue, 15 Mar 2022 08:07:39 +0300, Yura Sokolov
> wrote in
> > В Пн, 14/03/2022 в 14:57 +0300, Yura Sokolov пишет:
> > > В Пн, 14/03/2022 в 17:12 +0900, Kyotaro Horiguchi пи
В Пн, 14/03/2022 в 14:57 +0300, Yura Sokolov пишет:
> В Пн, 14/03/2022 в 17:12 +0900, Kyotaro Horiguchi пишет:
> > At Mon, 14 Mar 2022 09:15:11 +0300, Yura Sokolov
> > wrote in
> > > В Пн, 14/03/2022 в 14:31 +0900, Kyotaro Horiguchi пишет:
> > > > I'd lik
В Пн, 14/03/2022 в 17:12 +0900, Kyotaro Horiguchi пишет:
> At Mon, 14 Mar 2022 09:15:11 +0300, Yura Sokolov
> wrote in
> > В Пн, 14/03/2022 в 14:31 +0900, Kyotaro Horiguchi пишет:
> > > I'd like to ask you to remove nalloced from partitions then add a
> > >
? 32bit for
32 partitions. But wouldn't bitmap became contention point itself?
> No need to do something for the possible deviation issue.
---
regards
Yura Sokolov
killer?)
> Subject: [PATCH 3/3] reduce memory allocation for non-partitioned dynahash
>
> memory allocation -> memory allocations
For each dynahash instance single allocation were reduced.
I think, 'memory allocation' is correct.
Plural will be
reduce memory allocations for non
s, which need to be
> > treated
> >* just like permanent relations.
> >*
> >* The usage_count starts out at 1 so that the buffer can survive one
> >* clock-sweep pass.
>
> But if you think the current commet is fine, I don't
and !reuse cases but
> BufTableInsert doesn't and always does HASH_ASSIGN. That looks
> odd. We should use HASH_ENTER here. Thus I think it is more
> reasonable that HASH_ENTRY uses the stashed entry if exists and
> needed, or returns it to freelist if exists but not needed.
>
> What do you think about this?
Well... I don't like it but I don't mind either.
Code in HASH_ENTER and HASH_ASSIGN cases differs much.
On the other hand, probably it is possible to merge it carefuly.
I'll try.
-
regards
Yura Sokolov
В Пт, 11/03/2022 в 15:30 +0900, Kyotaro Horiguchi пишет:
> At Thu, 03 Mar 2022 01:35:57 +0300, Yura Sokolov
> wrote in
> > В Вт, 01/03/2022 в 10:24 +0300, Yura Sokolov пишет:
> > > Ok, here is v4.
> >
> > And here is v5.
> >
> > First, there
В Вт, 01/03/2022 в 10:24 +0300, Yura Sokolov пишет:
> Ok, here is v4.
And here is v5.
First, there was compilation error in Assert in dynahash.c .
Excuse me for not checking before sending previous version.
Second, I add third commit that reduces HASHHDR allocation
size for non-partitio
В Пт, 25/02/2022 в 09:38 +, Simon Riggs пишет:
> On Fri, 25 Feb 2022 at 09:24, Yura Sokolov wrote:
>
> > > This approach is cleaner than v1, but should also perform better
> > > because there will be a 1:1 relationship between a buffer and its
> > >
В Пт, 25/02/2022 в 09:01 -0800, Andres Freund пишет:
> Hi,
>
> On 2022-02-25 12:51:22 +0300, Yura Sokolov wrote:
> > > > +* The usage_count starts out at 1 so that the buffer can
> > > > survive one
> > > > +* clock-sweep pass.
> &
Hello, Andres
В Пт, 25/02/2022 в 00:04 -0800, Andres Freund пишет:
> Hi,
>
> On 2022-02-21 11:06:49 +0300, Yura Sokolov wrote:
> > From 04b07d0627ec65ba3327dc8338d59dbd15c405d8 Mon Sep 17 00:00:00 2001
> > From: Yura Sokolov
> > Date: Mon, 21 Feb 2022 08:49:03 +
Hello, Simon.
В Пт, 25/02/2022 в 04:35 +, Simon Riggs пишет:
> On Mon, 21 Feb 2022 at 08:06, Yura Sokolov wrote:
> > Good day, Kyotaro Horiguchi and hackers.
> >
> > В Чт, 17/02/2022 в 14:16 +0900, Kyotaro Horiguchi пишет:
> > > At Wed, 16 Feb 2022 10:40:56 +03
В Сб, 12/02/2022 в 16:56 +0530, Bharath Rupireddy пишет:
> On Fri, Feb 11, 2022 at 7:56 PM Yura Sokolov wrote:
> > В Сб, 16/10/2021 в 16:37 +0530, Bharath Rupireddy пишет:
> > > On Thu, Oct 14, 2021 at 10:56 AM Fujii Masao
> > > wrote:
> > > > On 20
Good day, Kyotaro Horiguchi and hackers.
В Чт, 17/02/2022 в 14:16 +0900, Kyotaro Horiguchi пишет:
> At Wed, 16 Feb 2022 10:40:56 +0300, Yura Sokolov
> wrote in
> > Hello, all.
> >
> > I thought about patch simplification, and tested version
> > without BufTable
and will attach graphs with
next message. Patch is attached here.
--
regards,
Yura Sokolov
Postgres Professional
y.soko...@postgrespro.ru
funny.fal...@gmail.com
From 7f430bdaa748456ed6b59f16f32ac0ea55644a66 Mon Sep 17 00:00:00 2001
From: Yura Sokolov
Date: Fri, 14 Jan 2022 02:28:36 +0300
wHashValue,
> LWLock *oldPartitionLock,
> LWLock *newPartitionLock
> );
Interesting suggestion, thanks. I'll think about.
It has downside of bringing LWLock knowdlege to dynahash.c .
But otherwise looks smart.
-
regards,
Yura Sokolov
ents should be written about new
usage case for `takenDuringRecovery`. May be this field should be renamed
at all?
And there are checks for `takenDuringRecovery` in `heapgetpage` and
`heapam_scan_sample_next_tuple`. Are this checks affected by the change?
Neither the preceding discussion nor commit message answer me.
---
regards
Yura Sokolov
Postgres Professional
y.soko...@postgrespro.ru
funny.fal...@gmail.com
orm an Assert(when_i_am_startup_proc &&
> autovacuum_not_running) (this looks a bit dirty though)? Instead, we
> can just enlarge the array in the master and be confident about the
> fact that the startup process always has one dedicated slot.
But this slot wont be used for most of cluster life. It will be just
waste.
And `Assert(there_is_startup_proc && autovacuum_not_running)` has
value on its own, hasn't it? So why doesn't add it with comment.
regards,
Yura Sokolov
В Вт, 25/01/2022 в 21:20 +1300, David Rowley пишет:
> On Tue, 25 Jan 2022 at 20:03, David Rowley wrote:
> > On Tue, 25 Jan 2022 at 17:35, Yura Sokolov wrote:
> > > And another attempt to fix tests volatility.
> >
> > FWIW, I had not really seen the point in addin
В Пн, 24/01/2022 в 16:24 +0300, Yura Sokolov пишет:
> В Вс, 23/01/2022 в 14:56 +0300, Yura Sokolov пишет:
> > В Чт, 20/01/2022 в 09:32 +1300, David Rowley пишет:
> > > On Fri, 31 Dec 2021 at 00:14, Yura Sokolov
> > > wrote:
> > > > Suggested quic
В Вс, 23/01/2022 в 14:56 +0300, Yura Sokolov пишет:
> В Чт, 20/01/2022 в 09:32 +1300, David Rowley пишет:
> > On Fri, 31 Dec 2021 at 00:14, Yura Sokolov wrote:
> > > Suggested quick (and valid) fix in the patch attached:
> > > - If Append has single child, then
В Чт, 20/01/2022 в 09:32 +1300, David Rowley пишет:
> On Fri, 31 Dec 2021 at 00:14, Yura Sokolov wrote:
> > Suggested quick (and valid) fix in the patch attached:
> > - If Append has single child, then copy its parallel awareness.
>
> I've been looking at this and I've gon
В Сб, 01/01/2022 в 15:19 +1300, David Rowley пишет:
> On Fri, 31 Dec 2021 at 00:14, Yura Sokolov wrote:
> > Problem:
> > - Append path is created with explicitely parallel_aware = true
> > - It has two child, one is trivial, other is parallel_aware = false .
> >
/m/17500.1551669976%40sss.pgh.pa.us
[2]
https://postgr.es/m/CAKJS1f_Wt_tL3S32R3wpU86zQjuHfbnZbFt0eqm%3DqcRFcdbLvw%40mail.gmail.com
regards
Yura Sokolov
y.soko...@postgrespro.ru
funny.fal...@gmail.com
From 47c6e161de4fc9d2d6eff45f427ebf49b4c9d11c Mon Sep 17 00:00:00 2001
From: Yura Sokolov
Date: Mon, 2
В Сб, 02/10/2021 в 01:25 +0300, Yura Sokolov пишет:
> Good day.
>
> I found some opportunity in Buffer Manager code in BufferAlloc
> function:
> - When valid buffer is evicted, BufferAlloc acquires two partition
> lwlocks: for partition for evicted block is in and partiti
В Вт, 26/10/2021 в 11:08 +0800, Sasasu пишет:
> On 2021/10/26 04:32, Yura Sokolov wrote:
> > And among others Adiantum looks best: it is fast even without hardware
> > acceleration,
>
> No, AES is fast on modern high-end hardware.
>
> on X86 AMD 3700X
> type
В Пн, 25/10/2021 в 12:12 -0400, Stephen Frost пишет:
> Greetings,
>
> * Yura Sokolov (y.soko...@postgrespro.ru) wrote:
> > В Чт, 21/10/2021 в 13:28 -0400, Stephen Frost пишет:
> > > I really don't think this is necessary. Similar to PageSetChecksumCopy
> > > and
cle/view/7360
[4] https://github.com/google/adiantum
[5]
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=059c2a4d8e164dccc3078e49e7f286023b019a98
---
regards
Yura Sokolov
y.soko...@postgrespro.ru
funny.fal...@gmail.com
В Пт, 18/12/2020 в 15:20 +0300, Konstantin Knizhnik пишет:
> Hi hackers,
>
> I am investigating incident with one of out customers: performance of
> the system isdropped dramatically.
> Stack traces of all backends can be found here:
> http://www.garret.ru/diag_20201217_102056.stacks_59644
>
I've made some remarks in related thread:
https://www.postgresql.org/message-id/flat/0A3221C70F24FB45833433255569204D1FB976EF@G01JPEXMBYT05
The new status of this patch is: Waiting on Author
E->segments` array.
I think, second option is more prefered:
- `DH_TYPE->segments[x]` inevitable accessed on every operation,
therefore why not store some info here?
- if nitems/used_items will be in `DH_TYPE->segments[x]`, then
hashtable iteration doesn't need bitmap at all - there will b
В Пт, 01/10/2021 в 15:46 -0700, Zhihong Yu wrote:
>
>
> On Fri, Oct 1, 2021 at 3:26 PM Yura Sokolov
> wrote:
> > Good day.
> >
> > I found some opportunity in Buffer Manager code in BufferAlloc
> > function:
> > - When valid buffer is evicted, Buff
,
Yura Sokolov
y.soko...@postgrespro.ru
funny.fal...@gmail.com
From a1606eaa124fc497763ed5e28e22cbc8f6443b33 Mon Sep 17 00:00:00 2001
From: Yura Sokolov
Date: Wed, 22 Sep 2021 13:10:37 +0300
Subject: [PATCH v0] bufmgr: do not acquire two partition locks.
Acquiring two partition locks leads to complex
.ru
funny.fal...@gmail.com
From 2afbc5a59c3ccd3fec14105aff40252eeaacf40c Mon Sep 17 00:00:00 2001
From: Yura Sokolov
Date: Wed, 22 Sep 2021 13:10:37 +0300
Subject: [PATCH] More gentle dynahash usage in buffer allocation.
When BufferAlloc reuses some valid buffer, there is no need
to go thro
x(0x0327ff01)
(where mix is a `__tmp` to `checksum` transformation)
regards,
Yura Sokolov
y.soko...@postgrespro.ru
funny.fal...@gmail.com
PS. Test program in Crystal language is attached and output for current
CHECKSUM_COMP implementation and "correct" (intended).
Excuse me for Crystal,
Ranier Vilela писал 2021-08-13 14:12:
Em sex., 13 de ago. de 2021 às 07:15, Andres Freund
escreveu:
Hi,
On 2021-08-13 12:44:17 +0300, Yura Sokolov wrote:
Andres Freund писал 2021-08-13 12:21:
Any chance you'd write a test for simplehash with such huge
amount of
values? It'd require
Andres Freund писал 2021-08-13 12:21:
Hi,
On 2021-08-10 11:52:59 +0300, Yura Sokolov wrote:
- sizemask is set only in SH_COMPUTE_PARAMETERS . And it is set in
this way:
/* now set size */
tb->size = size;
if (tb->size == SH_MAX_SIZE)
tb->siz
Ranier Vilela писал 2021-08-10 14:21:
Em ter., 10 de ago. de 2021 às 05:53, Yura Sokolov
escreveu:
I went to check SH_GROW and It is `SH_GROW(SH_TYPE *tb, uint32
newsize)`
:-(((
Therefore when `tb->size == SH_MAX_SIZE/2` and we call `SH_GROW(tb,
tb->size * 2)`,
then SH_GROW
== SH_MAX_SIZE/2` and we call `SH_GROW(tb,
tb->size * 2)`,
then SH_GROW(tb, 0) is called due to truncation.
And SH_COMPUTE_PARAMETERS is also accepts `uint32 newsize`.
Ahh... ok, patch is updated to fix this as well.
regards.
-
Yura Sokolov
y.soko...@postgrespro.ru
funny.fal...@gmail.com
Andres Freund писал 2021-08-06 06:49:
Hi,
On 2021-08-06 06:43:55 +0300, Yura Sokolov wrote:
Why don't use simplehash or something like that? Open-addressing
schemes
show superior cache locality.
I thought about that as well - but it doesn't really resolve the
question of
what we want
on-empty entry will be matched entry most of time, and
memory
lookup for key comparison will be amortized free.
Note that 8byte entry with fill factor 0.66 consumes amortized 12.12
byte,
while 16byte entry with fill factor 0.99 consumes amortized 16.16byte.
regards,
Yura Sokolov
y.soko...@postgrespro.ru
funny.fal...@gmail.com
In fact, my code uses bump allocator internally to avoid "per-allocation
overhead" of "aset", "slab" or "generational". And IntegerSet2 version
even uses it for all allocations since it has no reallocatable parts.
Well, if datastructure has reallocatable pa
Yura Sokolov писал 2021-07-29 18:29:
I've attached IntegerSet2 patch for pgtools repo and benchmark results.
Branch https://github.com/funny-falcon/pgtools/tree/integerset2
Strange web-mail client... I never can be sure what it will attach...
Reattach benchmark results
regards,
Yura
Masahiko Sawada писал 2021-07-29 17:29:
On Thu, Jul 29, 2021 at 8:03 PM Yura Sokolov
wrote:
Masahiko Sawada писал 2021-07-29 12:11:
> On Thu, Jul 29, 2021 at 3:53 AM Andres Freund
> wrote:
>>
>> Hi,
>>
>> On 2021-07-27 13:06:56 +0900, Masahiko Sawada wrot
esser memory consumption (and therefore better times) on
10x test, when page number exceed 2^23 (8M). It still produce "correct"
result for test since every page is filled in the same way.
Could you push your fixes for radix, please?
regards,
Yura Sokolov
y.soko...@postgrespro.ru
funny.fal...@gmail.com
intset replacement certainly. Using
same trick from radix_to_key it will store tids efficiently:
shift = pg_ceil_log2_32(MaxHeapTuplesPerPage);
tid_i = ItemPointerGetOffsetNumber(tid);
tid_i |= ItemPointerGetBlockNumber(tid) << shift;
Will do today's evening.
regards
Yura Sokol
ny-falcon/pgtools/tree/svtm/bdbench
regards,
Yura SokolovFrom 3a6c96cc705b1af412cf9300be6f676f6c5e4aa6 Mon Sep 17 00:00:00 2001
From: Yura Sokolov
Date: Sun, 25 Jul 2021 03:06:48 +0300
Subject: [PATCH] svtm - specialized vacuum tid map
---
bdbench/Makefile | 2 +-
bdbench/bdbench.c |
Fabien COELHO писал 2021-07-06 23:49:
Hello Yura,
However, I'm not enthousiastic at combining two methods depending on
the range, the function looks complex enough without that, so I would
suggest not to take this option. Also, the decision process adds to
the average cost, which is
Fabien COELHO писал 2021-07-06 09:13:
Hello Yura,
I believe most "range" values are small, much smaller than UINT32_MAX.
In this case, according to [1] fastest method is Lemire's one (I'd
take
original version from [2]) [...]
Yep.
I share your point that the range is more often 32 bits.
Fabien COELHO писал 2021-07-04 23:29:
The important property of determinism is that if I set a seed, and
then make an identical set of calls to the random API, the results
will be identical every time, so that it's possible to write tests
with predictable/repeatable results.
Hmmm… I like my
Fabien COELHO wrote 2021-07-03 11:45:
And a v5 where an unused test file does also compile if we insist.
About patch:
1. PostgreSQL source uses `uint64` and `uint32`, but not
`uint64_t`/`uint32_t`
2. I don't see why pg_prng_state could not be `typedef uint64
pg_prng_state[2];`
3. Then
Anastasia Lubennikova писал 2021-06-30 00:49:
Hi, hackers!
Many recently discussed features can make use of an extensible storage
manager API. Namely, storage level compression and encryption [1],
[2], [3], disk quota feature [4], SLRU storage changes [5], and any
other features that may want
Alvaro Herrera wrote 2021-06-08 00:07:
On 2021-May-27, Yura Sokolov wrote:
Alvaro Herrera писал 2021-05-26 23:59:
> I don't think they should do that. The portal remains open, and the
> libpq interface does that. The portal gets closed at end of transaction
> without the nee
Hi,
Andres Freund wrote 2021-05-31 00:07:
Hi,
On 2021-05-30 03:10:26 +0300, Yura Sokolov wrote:
While this result is not directly applied to stock PostgreSQL, I
believe
page compression is important for full_page_writes with
wal_compression
enabled. And probably when PostgreSQL is used
idn't measure impact on raw performance yet.
regards,
Yura Sokolov aka funny_falconcommit 6abfcaeb87fcb396c5e2dccd434ce2511314ff76
Author: Yura Sokolov
Date: Sun May 30 02:39:17 2021 +0300
Clear empty space in a page
Write zeroes to just cleared space in PageRepair
seek-able?
regards, tom lane
regards
Yura Sokolov
Alvaro Herrera писал 2021-05-26 23:59:
On 2021-May-25, Yura Sokolov wrote:
Tom Lane писал 2021-05-21 21:23:
> Yura Sokolov writes:
> > I propose to add PortalDrop at the 'if (completed)' branch of
> > exec_execute_message.
>
> This violates our wire protocol
Tom Lane писал 2021-05-21 21:23:
Yura Sokolov writes:
I propose to add PortalDrop at the 'if (completed)' branch of
exec_execute_message.
This violates our wire protocol specification, which
specifically says
If successfully created, a named portal object lasts till the end
Hi, hackers.
I've been playing with "autoprepared" patch, and have got isolation
"freeze-the-dead" test stuck on first VACUUM FREEZE statement.
After some research I found issue is reproduced with unmodified master
branch if extended protocol used. I've prepared ruby script for
demonstration
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