Re: PENDING_LIST_CLEANUP_SIZE - maximum size of GIN pending list Re: [HACKERS] HEAD seems to generate larger WAL regarding GIN index

[Fujii Masao]

On Tue, Aug 11, 2015 at 2:58 AM, Jeff Janes  wrote:
> On Thu, Oct 30, 2014 at 5:30 AM, Fujii Masao  wrote:
>>
>> On Thu, Oct 30, 2014 at 7:30 PM, Etsuro Fujita
>>  wrote:
>>
>> > +   {
>> > +   {"pending_list_cleanup_size", PGC_USERSET,
>> > CLIENT_CONN_STATEMENT,
>> > +   gettext_noop("Sets the maximum size of the
>> > pending
>> > list for GIN index."),
>> > +NULL,
>> > +   GUC_UNIT_KB
>> > +   },
>> > +   _list_cleanup_size,
>> > +   4096, 0, MAX_KILOBYTES,
>> > +   NULL, NULL, NULL
>> > +   },
>> >
>> > ISTM it'd be better to use RESOURCES_MEM, not CLIENT_CONN_STATEMENT. No?
>>
>> Yes if the pending list always exists in the memory. But not, IIUC.
>> Thought?
>>
>> > Also why not set min to 64, not to 0, in accoradance with that of
>> > work_mem?
>>
>> I'm OK to use 64. But I just chose 0 because I could not think of any
>> reasonable
>> reason why 64k is suitable as the minimum size of the pending list.
>> IOW, I have no idea about whether it's reasonable to use the min value of
>> work_mem as the min size of the pending list.
>
>
>
> I know I am late to the party here, but would like to have the minimum be 0,
> not 64.  As long as by zero, it means it doesn't insert anything into the
> pending list, rather than inserting and promptly cleaning it up.
>
> The reason for this is that if I am trying to decide what
> pending_list_cleanup_size I want to set for the index in the indexes storage
> parameters, the way to find that out is try a bunch of different ones
> through the guc while the index is still at the default of no overriding
> storage parameter.  It would be nice to try the fastupdate=off alternative
> (i.e. the same as pending_list_cleanup_size=0) without having to change the
> index itself and change the syntax used in the testing.

Sounds OK to me. So we should change the minimum values of both
gin_pending_list_limit GUC and storage parameters to 0? Or only GUC?

Regards,

-- 
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Re: PENDING_LIST_CLEANUP_SIZE - maximum size of GIN pending list Re: [HACKERS] HEAD seems to generate larger WAL regarding GIN index

[Jeff Janes]

On Thu, Oct 30, 2014 at 5:30 AM, Fujii Masao masao.fu...@gmail.com wrote:

 On Thu, Oct 30, 2014 at 7:30 PM, Etsuro Fujita
 fujita.ets...@lab.ntt.co.jp wrote:

  +   {
  +   {pending_list_cleanup_size, PGC_USERSET,
  CLIENT_CONN_STATEMENT,
  +   gettext_noop(Sets the maximum size of the
 pending
  list for GIN index.),
  +NULL,
  +   GUC_UNIT_KB
  +   },
  +   pending_list_cleanup_size,
  +   4096, 0, MAX_KILOBYTES,
  +   NULL, NULL, NULL
  +   },
 
  ISTM it'd be better to use RESOURCES_MEM, not CLIENT_CONN_STATEMENT. No?

 Yes if the pending list always exists in the memory. But not, IIUC.
 Thought?

  Also why not set min to 64, not to 0, in accoradance with that of
 work_mem?

 I'm OK to use 64. But I just chose 0 because I could not think of any
 reasonable
 reason why 64k is suitable as the minimum size of the pending list.
 IOW, I have no idea about whether it's reasonable to use the min value of
 work_mem as the min size of the pending list.



I know I am late to the party here, but would like to have the minimum be
0, not 64.  As long as by zero, it means it doesn't insert anything into
the pending list, rather than inserting and promptly cleaning it up.

The reason for this is that if I am trying to decide what
pending_list_cleanup_size I want to set for the index in the indexes
storage parameters, the way to find that out is try a bunch of different
ones through the guc while the index is still at the default of no
overriding storage parameter.  It would be nice to try the fastupdate=off
alternative (i.e. the same as pending_list_cleanup_size=0) without having
to change the index itself and change the syntax used in the testing.

Cheers,

Jeff

Re: PENDING_LIST_CLEANUP_SIZE - maximum size of GIN pending list Re: [HACKERS] HEAD seems to generate larger WAL regarding GIN index

[Fujii Masao]

On Wed, Nov 12, 2014 at 12:40 AM, Tom Lane t...@sss.pgh.pa.us wrote:
 Fujii Masao masao.fu...@gmail.com writes:
 On Tue, Nov 11, 2014 at 10:14 PM, Robert Haas robertmh...@gmail.com wrote:
 Not to kibitz too much after-the-fact, but wouldn't it be better to
 give this a name that has GIN in it somewhere?

 Maybe. gin_pending_list_cleanup_size? gin_pending_list_limit? Better name?

 gin_pending_list_limit sounds good to me.

OK, barring any objection, I will rename the reloption and GUC to
gin_pending_list_limit.

Regards,

-- 
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Re: PENDING_LIST_CLEANUP_SIZE - maximum size of GIN pending list Re: [HACKERS] HEAD seems to generate larger WAL regarding GIN index

[Fujii Masao]

On Wed, Nov 12, 2014 at 9:30 PM, Fujii Masao masao.fu...@gmail.com wrote:
 On Wed, Nov 12, 2014 at 12:40 AM, Tom Lane t...@sss.pgh.pa.us wrote:
 Fujii Masao masao.fu...@gmail.com writes:
 On Tue, Nov 11, 2014 at 10:14 PM, Robert Haas robertmh...@gmail.com wrote:
 Not to kibitz too much after-the-fact, but wouldn't it be better to
 give this a name that has GIN in it somewhere?

 Maybe. gin_pending_list_cleanup_size? gin_pending_list_limit? Better name?

 gin_pending_list_limit sounds good to me.

 OK, barring any objection, I will rename the reloption and GUC to
 gin_pending_list_limit.

Done.

Regards,

-- 
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Re: PENDING_LIST_CLEANUP_SIZE - maximum size of GIN pending list Re: [HACKERS] HEAD seems to generate larger WAL regarding GIN index

[Etsuro Fujita]

(2014/11/11 2:31), Fujii Masao wrote:

On Mon, Nov 10, 2014 at 4:15 PM, Etsuro Fujita

The patch looks good to me except for the following point:



*** a/src/backend/access/gin/ginfast.c
--- b/src/backend/access/gin/ginfast.c
***
*** 25,30 
--- 25,32 
   #include utils/memutils.h
   #include utils/rel.h

+ /* GUC parameter */
+ int   pending_list_cleanup_size = 0;

I think we need to initialize the GUC to boot_val, 4096 in this case.


No, IIUC basically the variable for GUC doesn't need to be initialized
to its default value. OTOH, it's also harmless to initialize it to the default.
I like the current code a bit because we don't need to change the initial
value again when we decide to change the default value of GUC.
I have no strong opinion about this, though.


OK, so if there are no objections of others, I'll mark this as Ready 
for Committer.


Thanks,

Best regards,
Etsuro Fujita


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Re: PENDING_LIST_CLEANUP_SIZE - maximum size of GIN pending list Re: [HACKERS] HEAD seems to generate larger WAL regarding GIN index

[Fujii Masao]

On Tue, Nov 11, 2014 at 7:01 PM, Etsuro Fujita
fujita.ets...@lab.ntt.co.jp wrote:
 (2014/11/11 2:31), Fujii Masao wrote:

 On Mon, Nov 10, 2014 at 4:15 PM, Etsuro Fujita

 The patch looks good to me except for the following point:


 *** a/src/backend/access/gin/ginfast.c
 --- b/src/backend/access/gin/ginfast.c
 ***
 *** 25,30 
 --- 25,32 
#include utils/memutils.h
#include utils/rel.h

 + /* GUC parameter */
 + int   pending_list_cleanup_size = 0;

 I think we need to initialize the GUC to boot_val, 4096 in this case.


 No, IIUC basically the variable for GUC doesn't need to be initialized
 to its default value. OTOH, it's also harmless to initialize it to the
 default.
 I like the current code a bit because we don't need to change the initial
 value again when we decide to change the default value of GUC.
 I have no strong opinion about this, though.


 OK, so if there are no objections of others, I'll mark this as Ready for
 Committer.

I just pushed this. Thanks!

Regards,

-- 
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Re: PENDING_LIST_CLEANUP_SIZE - maximum size of GIN pending list Re: [HACKERS] HEAD seems to generate larger WAL regarding GIN index

[Robert Haas]

On Tue, Nov 11, 2014 at 7:11 AM, Fujii Masao masao.fu...@gmail.com wrote:
 OK, so if there are no objections of others, I'll mark this as Ready for
 Committer.

 I just pushed this. Thanks!

Not to kibitz too much after-the-fact, but wouldn't it be better to
give this a name that has GIN in it somewhere?

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company


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Re: PENDING_LIST_CLEANUP_SIZE - maximum size of GIN pending list Re: [HACKERS] HEAD seems to generate larger WAL regarding GIN index

[Fujii Masao]

On Tue, Nov 11, 2014 at 10:14 PM, Robert Haas robertmh...@gmail.com wrote:
 On Tue, Nov 11, 2014 at 7:11 AM, Fujii Masao masao.fu...@gmail.com wrote:
 OK, so if there are no objections of others, I'll mark this as Ready for
 Committer.

 I just pushed this. Thanks!

 Not to kibitz too much after-the-fact, but wouldn't it be better to
 give this a name that has GIN in it somewhere?

Maybe. gin_pending_list_cleanup_size? gin_pending_list_limit? Better name?

Regards,

-- 
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Re: PENDING_LIST_CLEANUP_SIZE - maximum size of GIN pending list Re: [HACKERS] HEAD seems to generate larger WAL regarding GIN index

[Tom Lane]

Fujii Masao masao.fu...@gmail.com writes:
 On Tue, Nov 11, 2014 at 10:14 PM, Robert Haas robertmh...@gmail.com wrote:
 Not to kibitz too much after-the-fact, but wouldn't it be better to
 give this a name that has GIN in it somewhere?

 Maybe. gin_pending_list_cleanup_size? gin_pending_list_limit? Better name?

gin_pending_list_limit sounds good to me.

regards, tom lane


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Re: PENDING_LIST_CLEANUP_SIZE - maximum size of GIN pending list Re: [HACKERS] HEAD seems to generate larger WAL regarding GIN index

[Fujii Masao]

On Mon, Nov 10, 2014 at 4:15 PM, Etsuro Fujita
fujita.ets...@lab.ntt.co.jp wrote:
 (2014/11/06 23:38), Fujii Masao wrote:

 On Tue, Nov 4, 2014 at 12:04 PM, Etsuro Fujita
 fujita.ets...@lab.ntt.co.jp wrote:

 IIUC, I think that min = 0 disables fast update, so ISTM that it'd be
 appropriate to set min to some positive value.  And ISTM that the idea of
 using the min value of work_mem is not so bad.


 OK. I changed the min value to 64kB.

 *** 356,361  CREATE [ UNIQUE ] INDEX [ CONCURRENTLY ] [ replaceable
 class=parametername/
 --- 356,372 
/listitem
   /varlistentry
   /variablelist
 +variablelist
 +varlistentry
 + termliteralPENDING_LIST_CLEANUP_SIZE//term

 The above is still in uppercse.


 Fixed.

 Attached is the updated version of the patch. Thanks for the review!


 Thanks for the updating the patch!

 The patch looks good to me except for the following point:

Thanks for the review again!


 *** a/src/backend/access/gin/ginfast.c
 --- b/src/backend/access/gin/ginfast.c
 ***
 *** 25,30 
 --- 25,32 
   #include utils/memutils.h
   #include utils/rel.h

 + /* GUC parameter */
 + int   pending_list_cleanup_size = 0;

 I think we need to initialize the GUC to boot_val, 4096 in this case.

No, IIUC basically the variable for GUC doesn't need to be initialized
to its default value. OTOH, it's also harmless to initialize it to the default.
I like the current code a bit because we don't need to change the initial
value again when we decide to change the default value of GUC.
I have no strong opinion about this, though.

Regards,

-- 
Fujii Masao


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Re: PENDING_LIST_CLEANUP_SIZE - maximum size of GIN pending list Re: [HACKERS] HEAD seems to generate larger WAL regarding GIN index

[Etsuro Fujita]

(2014/11/06 23:38), Fujii Masao wrote:

On Tue, Nov 4, 2014 at 12:04 PM, Etsuro Fujita
fujita.ets...@lab.ntt.co.jp wrote:

IIUC, I think that min = 0 disables fast update, so ISTM that it'd be
appropriate to set min to some positive value.  And ISTM that the idea of
using the min value of work_mem is not so bad.


OK. I changed the min value to 64kB.


*** 356,361  CREATE [ UNIQUE ] INDEX [ CONCURRENTLY ] [ replaceable
class=parametername/
--- 356,372 
   /listitem
  /varlistentry
  /variablelist
+variablelist
+varlistentry
+ termliteralPENDING_LIST_CLEANUP_SIZE//term

The above is still in uppercse.


Fixed.

Attached is the updated version of the patch. Thanks for the review!


Thanks for the updating the patch!

The patch looks good to me except for the following point:

*** a/src/backend/access/gin/ginfast.c
--- b/src/backend/access/gin/ginfast.c
***
*** 25,30 
--- 25,32 
  #include utils/memutils.h
  #include utils/rel.h

+ /* GUC parameter */
+ int   pending_list_cleanup_size = 0;

I think we need to initialize the GUC to boot_val, 4096 in this case.

I asked the opinions of others about the config_group of the GUC.  But 
there seems no opinions, so I agree with Fujii-san's idea of assigning 
the GUC CLIENT_CONN_STATEMENT.


Thanks,

Best regards,
Etsuro Fujita


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Re: PENDING_LIST_CLEANUP_SIZE - maximum size of GIN pending list Re: [HACKERS] HEAD seems to generate larger WAL regarding GIN index

[Fujii Masao]

On Tue, Nov 4, 2014 at 12:04 PM, Etsuro Fujita
fujita.ets...@lab.ntt.co.jp wrote:
 IIUC, I think that min = 0 disables fast update, so ISTM that it'd be
 appropriate to set min to some positive value.  And ISTM that the idea of
 using the min value of work_mem is not so bad.

OK. I changed the min value to 64kB.

 *** 356,361  CREATE [ UNIQUE ] INDEX [ CONCURRENTLY ] [ replaceable
 class=parametername/
 --- 356,372 
   /listitem
  /varlistentry
  /variablelist
 +variablelist
 +varlistentry
 + termliteralPENDING_LIST_CLEANUP_SIZE//term

 The above is still in uppercse.

Fixed.

Attached is the updated version of the patch. Thanks for the review!

Regards,

-- 
Fujii Masao
*** a/doc/src/sgml/config.sgml
--- b/doc/src/sgml/config.sgml
***
*** 5911,5916  SET XML OPTION { DOCUMENT | CONTENT };
--- 5911,5937 
/listitem
   /varlistentry
  
+  varlistentry id=guc-pending-list-cleanup-size xreflabel=pending_list_cleanup_size
+   termvarnamepending_list_cleanup_size/varname (typeinteger/type)
+   indexterm
+primaryvarnamepending_list_cleanup_size/ configuration parameter/primary
+   /indexterm
+   /term
+   listitem
+para
+ Sets the maximum size of the GIN pending list which is used
+ when literalfastupdate/ is enabled. If the list grows
+ larger than this maximum size, it is cleaned up by moving
+ the entries in it to the main GIN data structure in bulk.
+ The default is four megabytes (literal4MB/). This setting
+ can be overridden for individual GIN indexes by changing
+ storage parameters.
+  See xref linkend=gin-fast-update and xref linkend=gin-tips
+  for more information.
+/para
+   /listitem
+  /varlistentry
+ 
   /variablelist
  /sect2
   sect2 id=runtime-config-client-format
*** a/doc/src/sgml/gin.sgml
--- b/doc/src/sgml/gin.sgml
***
*** 728,735 
 from the indexed item). As of productnamePostgreSQL/productname 8.4,
 acronymGIN/ is capable of postponing much of this work by inserting
 new tuples into a temporary, unsorted list of pending entries.
!When the table is vacuumed, or if the pending list becomes too large
!(larger than xref linkend=guc-work-mem), the entries are moved to the
 main acronymGIN/acronym data structure using the same bulk insert
 techniques used during initial index creation.  This greatly improves
 acronymGIN/acronym index update speed, even counting the additional
--- 728,735 
 from the indexed item). As of productnamePostgreSQL/productname 8.4,
 acronymGIN/ is capable of postponing much of this work by inserting
 new tuples into a temporary, unsorted list of pending entries.
!When the table is vacuumed, or if the pending list becomes larger than
!xref linkend=guc-pending-list-cleanup-size, the entries are moved to the
 main acronymGIN/acronym data structure using the same bulk insert
 techniques used during initial index creation.  This greatly improves
 acronymGIN/acronym index update speed, even counting the additional
***
*** 750,756 
para
 If consistent response time is more important than update speed,
 use of pending entries can be disabled by turning off the
!literalFASTUPDATE/literal storage parameter for a
 acronymGIN/acronym index.  See xref linkend=sql-createindex
 for details.
/para
--- 750,756 
para
 If consistent response time is more important than update speed,
 use of pending entries can be disabled by turning off the
!literalfastupdate/literal storage parameter for a
 acronymGIN/acronym index.  See xref linkend=sql-createindex
 for details.
/para
***
*** 812,829 
/varlistentry
  
varlistentry
!termxref linkend=guc-work-mem/term
 listitem
  para
   During a series of insertions into an existing acronymGIN/acronym
!  index that has literalFASTUPDATE/ enabled, the system will clean up
   the pending-entry list whenever the list grows larger than
!  varnamework_mem/.  To avoid fluctuations in observed response time,
!  it's desirable to have pending-list cleanup occur in the background
!  (i.e., via autovacuum).  Foreground cleanup operations can be avoided by
!  increasing varnamework_mem/ or making autovacuum more aggressive.
!  However, enlarging varnamework_mem/ means that if a foreground
!  cleanup does occur, it will take even longer.
  /para
 /listitem
/varlistentry
--- 812,837 
/varlistentry
  
varlistentry
!termxref linkend=guc-pending-list-cleanup-size/term
 listitem
  para
   During a series of insertions into an existing acronymGIN/acronym
!  index that has literalfastupdate/ enabled, the system will clean up
   the pending-entry list whenever the list grows larger than
!  

Re: PENDING_LIST_CLEANUP_SIZE - maximum size of GIN pending list Re: [HACKERS] HEAD seems to generate larger WAL regarding GIN index

[Etsuro Fujita]

(2014/10/30 21:30), Fujii Masao wrote:

On Thu, Oct 30, 2014 at 7:30 PM, Etsuro Fujita
fujita.ets...@lab.ntt.co.jp wrote:



Here are my review comments.

* The patch applies cleanly and make and make check run successfully.  I
think that the patch is mostly good.


Thanks! Attached is the updated version of the patch.


Thank you for updating the patch!


* In src/backend/utils/misc/guc.c:
+   {
+   {pending_list_cleanup_size, PGC_USERSET,
CLIENT_CONN_STATEMENT,
+   gettext_noop(Sets the maximum size of the pending
list for GIN index.),
+NULL,
+   GUC_UNIT_KB
+   },
+   pending_list_cleanup_size,
+   4096, 0, MAX_KILOBYTES,
+   NULL, NULL, NULL
+   },

ISTM it'd be better to use RESOURCES_MEM, not CLIENT_CONN_STATEMENT. No?


Yes if the pending list always exists in the memory. But not, IIUC. Thought?


Exactly.  But I think we can expect that in many cases, since I think 
that the users would often set the GUC to a small value to the extent 
that most of the pending list pages would be cached by shared buffer, to 
maintain *search* performance.


I'd like to hear the opinions of others about the category for the GUC.


Also why not set min to 64, not to 0, in accoradance with that of work_mem?


I'm OK to use 64. But I just chose 0 because I could not think of any reasonable
reason why 64k is suitable as the minimum size of the pending list.
IOW, I have no idea about whether it's reasonable to use the min value of
work_mem as the min size of the pending list.


IIUC, I think that min = 0 disables fast update, so ISTM that it'd be 
appropriate to set min to some positive value.  And ISTM that the idea 
of using the min value of work_mem is not so bad.



* In doc/src/sgml/ref/create_index.sgml:
+ termliteralPENDING_LIST_CLEANUP_SIZE//term

IMHO, it seems to me better for this variable to be in lowercase in
accordance with the GUC version.


Using lowercase only for pending_list_cleanup_size and uppercase for
other options
looks strange to me. What about using lowercase for all the storage options?


+1


I changed the document in that way.


*** 356,361  CREATE [ UNIQUE ] INDEX [ CONCURRENTLY ] [ replaceable 
class=parametername/

--- 356,372 
  /listitem
 /varlistentry
 /variablelist
+variablelist
+varlistentry
+ termliteralPENDING_LIST_CLEANUP_SIZE//term

The above is still in uppercse.

Thanks,

Best regards,
Etsuro Fujita


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Re: PENDING_LIST_CLEANUP_SIZE - maximum size of GIN pending list Re: [HACKERS] HEAD seems to generate larger WAL regarding GIN index

[Etsuro Fujita]

(2014/10/09 11:49), Etsuro Fujita wrote:

(2014/10/08 22:51), Fujii Masao wrote:

On Wed, Sep 24, 2014 at 11:10 AM, Etsuro Fujita
fujita.ets...@lab.ntt.co.jp wrote:

On Wed, Sep 10, 2014 at 10:37 PM, Alvaro Herrera
alvhe...@2ndquadrant.com wrote:

Fujii Masao wrote:

On Wed, Sep 10, 2014 at 12:15 PM, Etsuro Fujita
fujita.ets...@lab.ntt.co.jp wrote:



PENDING_LIST_CLEANUP_SIZE and work_mem, for this setting.
Wouldn't it be easy-to-use to have only one parameter,
PENDING_LIST_CLEANUP_SIZE?  How about setting
PENDING_LIST_CLEANUP_SIZE
to
work_mem as the default value when running the CREATE INDEX command?



So what about introduing pending_list_cleanup_size also as GUC?
That is, users can set the threshold by using either the reloption or
GUC.



Yes, I think having both a GUC and a reloption makes sense -- the GUC
applies to all indexes, and can be tweaked for individual indexes
using
the reloption.



OK, I'd vote for your idea of having both the GUC and the reloption.
So, I
think the patch needs to be updated.  Fujii-san, what plan do you
have about
the patch?



Please see the attached patch. In this patch, I introduced the GUC
parameter,
pending_list_cleanup_size. I chose 4MB as the default value of the
parameter.
But do you have any better idea about that default value?



It seems reasonable to me that the GUC has the same default value as
work_mem.  So, +1 for the default value of 4MB.



BTW, I moved the CommitFest entry of this patch to next CF 2014-10.



OK, I'll review the patch in the CF.


Thank you for updating the patch!  Here are my review comments.

* The patch applies cleanly and make and make check run successfully.  I 
think that the patch is mostly good.


* In src/backend/utils/misc/guc.c:
+   {
+   {pending_list_cleanup_size, PGC_USERSET, 
CLIENT_CONN_STATEMENT,
+ 			gettext_noop(Sets the maximum size of the pending list for GIN 
index.),

+NULL,
+   GUC_UNIT_KB
+   },
+   pending_list_cleanup_size,
+   4096, 0, MAX_KILOBYTES,
+   NULL, NULL, NULL
+   },

ISTM it'd be better to use RESOURCES_MEM, not CLIENT_CONN_STATEMENT. No? 
 Also why not set min to 64, not to 0, in accoradance with that of 
work_mem?


* In src/backend/utils/misc/postgresql.conf.sample:
Likewise, why not put this variable in the section of RESOURCE USAGE, 
not in that of CLIENT CONNECTION DEFAULTS.


* In src/backend/access/common/reloptions.c:
+   {
+   {
+   pending_list_cleanup_size,
+   Maximum size of the pending list for this GIN index, in 
kilobytes.,
+   RELOPT_KIND_GIN
+   },
+   -1, 0, MAX_KILOBYTES
+   },

As in guc.c, why not set min to 64, not to 0?

* In src/include/access/gin.h:
  /* GUC parameter */
  extern PGDLLIMPORT int GinFuzzySearchLimit;
+ extern int pending_list_cleanup_size;

The comment should be GUC parameters.

* In src/backend/access/gin/ginfast.c:
+ /* GUC parameter */
+ int   pending_list_cleanup_size = 0;

Do we need to substitute 0 for pending_list_cleanup_size?

* In doc/src/sgml/config.sgml:
+  varlistentry id=guc-pending-list-cleanup-size 
xreflabel=pending_list_cleanup_size
+   termvarnamepending_list_cleanup_size/varname 
(typeinteger/type)


As in postgresql.conf.sample, ISTM it'd be better to explain this 
variable in the section of Resource Consumption (maybe in Memory), not 
in that of Client Connection Defaults.


* In doc/src/sgml/gin.sgml:
!  literalpending_list_cleanup_size/. To avoid fluctuations in 
observed


ISTM it'd be better to use varname for pending_list_cleanup_size, not 
literal, here.


* In doc/src/sgml/ref/create_index.sgml:
+ termliteralPENDING_LIST_CLEANUP_SIZE//term

IMHO, it seems to me better for this variable to be in lowercase in 
accordance with the GUC version.  Also, I think that the words GIN 
indexes accept a different parameter: in the section of Index Storage 
Parameters in this reference page would be GIN indexes accept 
different parameters:.


Sorry for the delay in reviewing the patch.

Best regards,
Etsuro Fujita


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Re: PENDING_LIST_CLEANUP_SIZE - maximum size of GIN pending list Re: [HACKERS] HEAD seems to generate larger WAL regarding GIN index

[Fujii Masao]

On Thu, Oct 30, 2014 at 7:30 PM, Etsuro Fujita
fujita.ets...@lab.ntt.co.jp wrote:
 (2014/10/09 11:49), Etsuro Fujita wrote:

 (2014/10/08 22:51), Fujii Masao wrote:

 On Wed, Sep 24, 2014 at 11:10 AM, Etsuro Fujita
 fujita.ets...@lab.ntt.co.jp wrote:

 On Wed, Sep 10, 2014 at 10:37 PM, Alvaro Herrera
 alvhe...@2ndquadrant.com wrote:

 Fujii Masao wrote:

 On Wed, Sep 10, 2014 at 12:15 PM, Etsuro Fujita
 fujita.ets...@lab.ntt.co.jp wrote:


 PENDING_LIST_CLEANUP_SIZE and work_mem, for this setting.
 Wouldn't it be easy-to-use to have only one parameter,
 PENDING_LIST_CLEANUP_SIZE?  How about setting
 PENDING_LIST_CLEANUP_SIZE
 to
 work_mem as the default value when running the CREATE INDEX command?


 So what about introduing pending_list_cleanup_size also as GUC?
 That is, users can set the threshold by using either the reloption or
 GUC.


 Yes, I think having both a GUC and a reloption makes sense -- the GUC
 applies to all indexes, and can be tweaked for individual indexes
 using
 the reloption.


 OK, I'd vote for your idea of having both the GUC and the reloption.
 So, I
 think the patch needs to be updated.  Fujii-san, what plan do you
 have about
 the patch?


 Please see the attached patch. In this patch, I introduced the GUC
 parameter,
 pending_list_cleanup_size. I chose 4MB as the default value of the
 parameter.
 But do you have any better idea about that default value?


 It seems reasonable to me that the GUC has the same default value as
 work_mem.  So, +1 for the default value of 4MB.


 BTW, I moved the CommitFest entry of this patch to next CF 2014-10.


 OK, I'll review the patch in the CF.


 Thank you for updating the patch!  Here are my review comments.

 * The patch applies cleanly and make and make check run successfully.  I
 think that the patch is mostly good.

Thanks! Attached is the updated version of the patch.

 * In src/backend/utils/misc/guc.c:
 +   {
 +   {pending_list_cleanup_size, PGC_USERSET,
 CLIENT_CONN_STATEMENT,
 +   gettext_noop(Sets the maximum size of the pending
 list for GIN index.),
 +NULL,
 +   GUC_UNIT_KB
 +   },
 +   pending_list_cleanup_size,
 +   4096, 0, MAX_KILOBYTES,
 +   NULL, NULL, NULL
 +   },

 ISTM it'd be better to use RESOURCES_MEM, not CLIENT_CONN_STATEMENT. No?

Yes if the pending list always exists in the memory. But not, IIUC. Thought?

 Also why not set min to 64, not to 0, in accoradance with that of work_mem?

I'm OK to use 64. But I just chose 0 because I could not think of any reasonable
reason why 64k is suitable as the minimum size of the pending list.
IOW, I have no idea about whether it's reasonable to use the min value of
work_mem as the min size of the pending list.

 * In src/backend/utils/misc/postgresql.conf.sample:
 Likewise, why not put this variable in the section of RESOURCE USAGE, not in
 that of CLIENT CONNECTION DEFAULTS.

Same as above.


 * In src/backend/access/common/reloptions.c:
 +   {
 +   {
 +   pending_list_cleanup_size,
 +   Maximum size of the pending list for this GIN
 index, in kilobytes.,
 +   RELOPT_KIND_GIN
 +   },
 +   -1, 0, MAX_KILOBYTES
 +   },

 As in guc.c, why not set min to 64, not to 0?

Same as above.

 * In src/include/access/gin.h:
   /* GUC parameter */
   extern PGDLLIMPORT int GinFuzzySearchLimit;
 + extern int pending_list_cleanup_size;

 The comment should be GUC parameters.

Yes, fixed.

 * In src/backend/access/gin/ginfast.c:
 + /* GUC parameter */
 + int   pending_list_cleanup_size = 0;

 Do we need to substitute 0 for pending_list_cleanup_size?

Same as above.


 * In doc/src/sgml/config.sgml:
 +  varlistentry id=guc-pending-list-cleanup-size
 xreflabel=pending_list_cleanup_size
 +   termvarnamepending_list_cleanup_size/varname
 (typeinteger/type)

 As in postgresql.conf.sample, ISTM it'd be better to explain this variable
 in the section of Resource Consumption (maybe in Memory), not in that of
 Client Connection Defaults.

Same as above.

 * In doc/src/sgml/gin.sgml:
 !  literalpending_list_cleanup_size/. To avoid fluctuations in
 observed

 ISTM it'd be better to use varname for pending_list_cleanup_size, not
 literal, here.

Yes, fixed.

 * In doc/src/sgml/ref/create_index.sgml:
 + termliteralPENDING_LIST_CLEANUP_SIZE//term

 IMHO, it seems to me better for this variable to be in lowercase in
 accordance with the GUC version.

Using lowercase only for pending_list_cleanup_size and uppercase for
other options
looks strange to me. What about using lowercase for all the storage options?
I changed the document in that way.

 Also, I think that the words GIN indexes
 accept a different parameter: in the section of Index Storage Parameters
 in this reference page would be GIN indexes accept different parameters:.

Yes, 

Re: PENDING_LIST_CLEANUP_SIZE - maximum size of GIN pending list Re: [HACKERS] HEAD seems to generate larger WAL regarding GIN index

[Fujii Masao]

On Wed, Sep 24, 2014 at 11:10 AM, Etsuro Fujita
fujita.ets...@lab.ntt.co.jp wrote:
 (2014/09/13 2:42), Fujii Masao wrote:

 On Wed, Sep 10, 2014 at 10:37 PM, Alvaro Herrera
 alvhe...@2ndquadrant.com wrote:

 Fujii Masao wrote:

 On Wed, Sep 10, 2014 at 12:15 PM, Etsuro Fujita
 fujita.ets...@lab.ntt.co.jp wrote:


 PENDING_LIST_CLEANUP_SIZE and work_mem, for this setting.
 Wouldn't it be easy-to-use to have only one parameter,
 PENDING_LIST_CLEANUP_SIZE?  How about setting PENDING_LIST_CLEANUP_SIZE
 to
 work_mem as the default value when running the CREATE INDEX command?


 That's an idea. But there might be some users who want to change
 the cleanup size per session like they can do by setting work_mem,
 and your idea would prevent them from doing that...

 So what about introduing pending_list_cleanup_size also as GUC?
 That is, users can set the threshold by using either the reloption or
 GUC.


 Yes, I think having both a GUC and a reloption makes sense -- the GUC
 applies to all indexes, and can be tweaked for individual indexes using
 the reloption.


 Agreed.

 I'm not sure about the idea of being able to change it per session,
 though.  Do you mean that you would like insert processes use a very
 large value so that they can just append new values to the pending list,
 and have vacuum use a small value so that it cleans up as soon as it
 runs?  Two things: 1. we could have an autovacuum_ reloption which
 only changes what autovacuum does; 2. we could have autovacuum run
 index cleanup actions separately from actual vacuuming.


 Yes, I was thinking something like that. But if autovacuum
 has already been able to handle that, it's nice. Anyway,
 as you pointed out, it's better to have both GUC and reloption
 for the cleanup size of pending list.


 OK, I'd vote for your idea of having both the GUC and the reloption. So, I
 think the patch needs to be updated.  Fujii-san, what plan do you have about
 the patch?

Please see the attached patch. In this patch, I introduced the GUC parameter,
pending_list_cleanup_size. I chose 4MB as the default value of the parameter.
But do you have any better idea about that default value?

BTW, I moved the CommitFest entry of this patch to next CF 2014-10.

Regards,

-- 
Fujii Masao
*** a/doc/src/sgml/config.sgml
--- b/doc/src/sgml/config.sgml
***
*** 5907,5912  SET XML OPTION { DOCUMENT | CONTENT };
--- 5907,5933 
/listitem
   /varlistentry
  
+  varlistentry id=guc-pending-list-cleanup-size xreflabel=pending_list_cleanup_size
+   termvarnamepending_list_cleanup_size/varname (typeinteger/type)
+   indexterm
+primaryvarnamepending_list_cleanup_size/ configuration parameter/primary
+   /indexterm
+   /term
+   listitem
+para
+ Sets the maximum size of the GIN pending list which is used
+ when literalFASTUPDATE/ is enabled. If the list grows
+ larger than this maximum size, it is cleaned up by moving
+ the entries in it to the main GIN data structure in bulk.
+ The default is four megabytes (literal4MB/). This setting
+ can be overridden for individual GIN indexes by changing
+ storage parameters.
+  See xref linkend=gin-fast-update and xref linkend=gin-tips
+  for more information.
+/para
+   /listitem
+  /varlistentry
+ 
   /variablelist
  /sect2
   sect2 id=runtime-config-client-format
*** a/doc/src/sgml/gin.sgml
--- b/doc/src/sgml/gin.sgml
***
*** 728,735 
 from the indexed item). As of productnamePostgreSQL/productname 8.4,
 acronymGIN/ is capable of postponing much of this work by inserting
 new tuples into a temporary, unsorted list of pending entries.
!When the table is vacuumed, or if the pending list becomes too large
!(larger than xref linkend=guc-work-mem), the entries are moved to the
 main acronymGIN/acronym data structure using the same bulk insert
 techniques used during initial index creation.  This greatly improves
 acronymGIN/acronym index update speed, even counting the additional
--- 728,735 
 from the indexed item). As of productnamePostgreSQL/productname 8.4,
 acronymGIN/ is capable of postponing much of this work by inserting
 new tuples into a temporary, unsorted list of pending entries.
!When the table is vacuumed, or if the pending list becomes larger than
!xref linkend=guc-pending-list-cleanup-size, the entries are moved to the
 main acronymGIN/acronym data structure using the same bulk insert
 techniques used during initial index creation.  This greatly improves
 acronymGIN/acronym index update speed, even counting the additional
***
*** 812,829 
/varlistentry
  
varlistentry
!termxref linkend=guc-work-mem/term
 listitem
  para
   During a series of insertions into an existing acronymGIN/acronym
   index that has literalFASTUPDATE/ enabled, the 

Re: PENDING_LIST_CLEANUP_SIZE - maximum size of GIN pending list Re: [HACKERS] HEAD seems to generate larger WAL regarding GIN index

[Etsuro Fujita]

(2014/10/08 22:51), Fujii Masao wrote:

On Wed, Sep 24, 2014 at 11:10 AM, Etsuro Fujita
fujita.ets...@lab.ntt.co.jp wrote:



On Wed, Sep 10, 2014 at 10:37 PM, Alvaro Herrera
alvhe...@2ndquadrant.com wrote:

Fujii Masao wrote:

On Wed, Sep 10, 2014 at 12:15 PM, Etsuro Fujita
fujita.ets...@lab.ntt.co.jp wrote:



PENDING_LIST_CLEANUP_SIZE and work_mem, for this setting.
Wouldn't it be easy-to-use to have only one parameter,
PENDING_LIST_CLEANUP_SIZE?  How about setting PENDING_LIST_CLEANUP_SIZE
to
work_mem as the default value when running the CREATE INDEX command?



So what about introduing pending_list_cleanup_size also as GUC?
That is, users can set the threshold by using either the reloption or
GUC.



Yes, I think having both a GUC and a reloption makes sense -- the GUC
applies to all indexes, and can be tweaked for individual indexes using
the reloption.



OK, I'd vote for your idea of having both the GUC and the reloption. So, I
think the patch needs to be updated.  Fujii-san, what plan do you have about
the patch?



Please see the attached patch. In this patch, I introduced the GUC parameter,
pending_list_cleanup_size. I chose 4MB as the default value of the parameter.
But do you have any better idea about that default value?


It seems reasonable to me that the GUC has the same default value as 
work_mem.  So, +1 for the default value of 4MB.



BTW, I moved the CommitFest entry of this patch to next CF 2014-10.


OK, I'll review the patch in the CF.

Thanks,

Best regards,
Etsuro Fujita


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Re: PENDING_LIST_CLEANUP_SIZE - maximum size of GIN pending list Re: [HACKERS] HEAD seems to generate larger WAL regarding GIN index

[Etsuro Fujita]

(2014/09/13 2:42), Fujii Masao wrote:

On Wed, Sep 10, 2014 at 10:37 PM, Alvaro Herrera
alvhe...@2ndquadrant.com wrote:

Fujii Masao wrote:

On Wed, Sep 10, 2014 at 12:15 PM, Etsuro Fujita
fujita.ets...@lab.ntt.co.jp wrote:



PENDING_LIST_CLEANUP_SIZE and work_mem, for this setting.
Wouldn't it be easy-to-use to have only one parameter,
PENDING_LIST_CLEANUP_SIZE?  How about setting PENDING_LIST_CLEANUP_SIZE to
work_mem as the default value when running the CREATE INDEX command?


That's an idea. But there might be some users who want to change
the cleanup size per session like they can do by setting work_mem,
and your idea would prevent them from doing that...

So what about introduing pending_list_cleanup_size also as GUC?
That is, users can set the threshold by using either the reloption or
GUC.


Yes, I think having both a GUC and a reloption makes sense -- the GUC
applies to all indexes, and can be tweaked for individual indexes using
the reloption.


Agreed.


I'm not sure about the idea of being able to change it per session,
though.  Do you mean that you would like insert processes use a very
large value so that they can just append new values to the pending list,
and have vacuum use a small value so that it cleans up as soon as it
runs?  Two things: 1. we could have an autovacuum_ reloption which
only changes what autovacuum does; 2. we could have autovacuum run
index cleanup actions separately from actual vacuuming.


Yes, I was thinking something like that. But if autovacuum
has already been able to handle that, it's nice. Anyway,
as you pointed out, it's better to have both GUC and reloption
for the cleanup size of pending list.


OK, I'd vote for your idea of having both the GUC and the reloption. 
So, I think the patch needs to be updated.  Fujii-san, what plan do you 
have about the patch?


Sorry for the delay.

Thanks,

Best regards,
Etsuro Fujita


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Re: PENDING_LIST_CLEANUP_SIZE - maximum size of GIN pending list Re: [HACKERS] HEAD seems to generate larger WAL regarding GIN index

[Fujii Masao]

On Wed, Sep 10, 2014 at 10:37 PM, Alvaro Herrera
alvhe...@2ndquadrant.com wrote:
 Fujii Masao wrote:
 On Wed, Sep 10, 2014 at 12:15 PM, Etsuro Fujita
 fujita.ets...@lab.ntt.co.jp wrote:

  PENDING_LIST_CLEANUP_SIZE and work_mem, for this setting.
  Wouldn't it be easy-to-use to have only one parameter,
  PENDING_LIST_CLEANUP_SIZE?  How about setting PENDING_LIST_CLEANUP_SIZE to
  work_mem as the default value when running the CREATE INDEX command?

 That's an idea. But there might be some users who want to change
 the cleanup size per session like they can do by setting work_mem,
 and your idea would prevent them from doing that...

 So what about introduing pending_list_cleanup_size also as GUC?
 That is, users can set the threshold by using either the reloption or
 GUC.

 Yes, I think having both a GUC and a reloption makes sense -- the GUC
 applies to all indexes, and can be tweaked for individual indexes using
 the reloption.

Agreed.

 I'm not sure about the idea of being able to change it per session,
 though.  Do you mean that you would like insert processes use a very
 large value so that they can just append new values to the pending list,
 and have vacuum use a small value so that it cleans up as soon as it
 runs?  Two things: 1. we could have an autovacuum_ reloption which
 only changes what autovacuum does; 2. we could have autovacuum run
 index cleanup actions separately from actual vacuuming.

Yes, I was thinking something like that. But if autovacuum
has already been able to handle that, it's nice. Anyway,
as you pointed out, it's better to have both GUC and reloption
for the cleanup size of pending list.

Regards,

-- 
Fujii Masao


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Re: PENDING_LIST_CLEANUP_SIZE - maximum size of GIN pending list Re: [HACKERS] HEAD seems to generate larger WAL regarding GIN index

[Etsuro Fujita]

(2014/09/10 12:31), Fujii Masao wrote:

On Wed, Sep 10, 2014 at 12:15 PM, Etsuro Fujita
fujita.ets...@lab.ntt.co.jp wrote:

(2014/09/09 22:17), Fujii Masao wrote:

Attached is the updated version of the patch.



I took a quick review on the patch.  It looks good to me,



but one thing I'm
concerned about is

You wrote:

The attached patch introduces the GIN index storage parameter
PENDING_LIST_CLEANUP_SIZE which specifies the maximum size of
GIN pending list. If it's not set, work_mem is used as that maximum
size,
instead. So this patch doesn't break the existing application which
currently uses work_mem as the threshold of cleanup operation of
the pending list. It has only not to set PENDING_LIST_CLEANUP_SIZE.


As you mentioned, I think it's important to consider for the existing
applications, but I'm wondering if it would be a bit confusing users to have
two parameters,


Yep.


PENDING_LIST_CLEANUP_SIZE and work_mem, for this setting.
Wouldn't it be easy-to-use to have only one parameter,
PENDING_LIST_CLEANUP_SIZE?  How about setting PENDING_LIST_CLEANUP_SIZE to
work_mem as the default value when running the CREATE INDEX command?


That's an idea. But there might be some users who want to change
the cleanup size per session like they can do by setting work_mem,
and your idea would prevent them from doing that...


Why not use ALTER INDEX ... SET (PENDING_LIST_CLEANUP_SIZE= ...)?  Maybe 
I'm missing something, though.



So what about introduing pending_list_cleanup_size also as GUC?
That is, users can set the threshold by using either the reloption or
GUC.


Yeah, that's an idea.  So, I'd like to hear the opinions of others.

Thanks,

Best regards,
Etsuro Fujita


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Re: PENDING_LIST_CLEANUP_SIZE - maximum size of GIN pending list Re: [HACKERS] HEAD seems to generate larger WAL regarding GIN index

[Fujii Masao]

On Wed, Sep 10, 2014 at 5:35 PM, Etsuro Fujita
fujita.ets...@lab.ntt.co.jp wrote:
 (2014/09/10 12:31), Fujii Masao wrote:

 On Wed, Sep 10, 2014 at 12:15 PM, Etsuro Fujita
 fujita.ets...@lab.ntt.co.jp wrote:

 (2014/09/09 22:17), Fujii Masao wrote:

 Attached is the updated version of the patch.


 I took a quick review on the patch.  It looks good to me,


 but one thing I'm
 concerned about is

 You wrote:

 The attached patch introduces the GIN index storage parameter
 PENDING_LIST_CLEANUP_SIZE which specifies the maximum size of
 GIN pending list. If it's not set, work_mem is used as that maximum
 size,
 instead. So this patch doesn't break the existing application which
 currently uses work_mem as the threshold of cleanup operation of
 the pending list. It has only not to set PENDING_LIST_CLEANUP_SIZE.


 As you mentioned, I think it's important to consider for the existing
 applications, but I'm wondering if it would be a bit confusing users to
 have
 two parameters,


 Yep.

 PENDING_LIST_CLEANUP_SIZE and work_mem, for this setting.
 Wouldn't it be easy-to-use to have only one parameter,
 PENDING_LIST_CLEANUP_SIZE?  How about setting PENDING_LIST_CLEANUP_SIZE
 to
 work_mem as the default value when running the CREATE INDEX command?


 That's an idea. But there might be some users who want to change
 the cleanup size per session like they can do by setting work_mem,
 and your idea would prevent them from doing that...


 Why not use ALTER INDEX ... SET (PENDING_LIST_CLEANUP_SIZE= ...)?  Maybe I'm
 missing something, though.

It takes AccessExclusive lock and has an effect on every sessions
(not only specified session).

Regards,

-- 
Fujii Masao


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Re: PENDING_LIST_CLEANUP_SIZE - maximum size of GIN pending list Re: [HACKERS] HEAD seems to generate larger WAL regarding GIN index

[Alvaro Herrera]

Fujii Masao wrote:
 On Wed, Sep 10, 2014 at 12:15 PM, Etsuro Fujita
 fujita.ets...@lab.ntt.co.jp wrote:

  PENDING_LIST_CLEANUP_SIZE and work_mem, for this setting.
  Wouldn't it be easy-to-use to have only one parameter,
  PENDING_LIST_CLEANUP_SIZE?  How about setting PENDING_LIST_CLEANUP_SIZE to
  work_mem as the default value when running the CREATE INDEX command?
 
 That's an idea. But there might be some users who want to change
 the cleanup size per session like they can do by setting work_mem,
 and your idea would prevent them from doing that...
 
 So what about introduing pending_list_cleanup_size also as GUC?
 That is, users can set the threshold by using either the reloption or
 GUC.

Yes, I think having both a GUC and a reloption makes sense -- the GUC
applies to all indexes, and can be tweaked for individual indexes using
the reloption.

I'm not sure about the idea of being able to change it per session,
though.  Do you mean that you would like insert processes use a very
large value so that they can just append new values to the pending list,
and have vacuum use a small value so that it cleans up as soon as it
runs?  Two things: 1. we could have an autovacuum_ reloption which
only changes what autovacuum does; 2. we could have autovacuum run
index cleanup actions separately from actual vacuuming.

-- 
Álvaro Herrerahttp://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Training  Services


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Re: PENDING_LIST_CLEANUP_SIZE - maximum size of GIN pending list Re: [HACKERS] HEAD seems to generate larger WAL regarding GIN index

[Fujii Masao]

On Tue, Sep 9, 2014 at 1:28 AM, Jeff Janes jeff.ja...@gmail.com wrote:
 On Sun, Aug 17, 2014 at 7:46 PM, Fujii Masao masao.fu...@gmail.com wrote:


 Thanks for reviewing the patch! ISTM that I failed to make the patch from
 my git repository... Attached is the rebased version.



 I get some compiler warnings on v2 of this patch:

 reloptions.c:219: warning: excess elements in struct initializer
 reloptions.c:219: warning: (near initialization for 'intRelOpts[15]')

Thanks for testing the patch!
Attached is the updated version of the patch.

Previously the patch depended on another infrastructure patch
(which allows a user to specify the unit in reloption (*1)). But that
infrastructure patch has serious problem and it's not easy to fix
the problem. So I changed the patch so that it doesn't depend on
that infrastructure patch at all. Even without the infrastructure
patch, the feature that this patch introduces is useful.

Also I added the regression test into the patch.

(*1)
http://www.postgresql.org/message-id/CAHGQGwEanQ_e8WLHL25=bm_8z5zkyzw0k0yir+kdmv2hgne...@mail.gmail.com

Regards,

-- 
Fujii Masao
*** a/doc/src/sgml/gin.sgml
--- b/doc/src/sgml/gin.sgml
***
*** 728,735 
 from the indexed item). As of productnamePostgreSQL/productname 8.4,
 acronymGIN/ is capable of postponing much of this work by inserting
 new tuples into a temporary, unsorted list of pending entries.
!When the table is vacuumed, or if the pending list becomes too large
!(larger than xref linkend=guc-work-mem), the entries are moved to the
 main acronymGIN/acronym data structure using the same bulk insert
 techniques used during initial index creation.  This greatly improves
 acronymGIN/acronym index update speed, even counting the additional
--- 728,736 
 from the indexed item). As of productnamePostgreSQL/productname 8.4,
 acronymGIN/ is capable of postponing much of this work by inserting
 new tuples into a temporary, unsorted list of pending entries.
!When the table is vacuumed, or if the pending list becomes larger than
!literalPENDING_LIST_CLEANUP_SIZE/literal (or
!xref linkend=guc-work-mem if not set), the entries are moved to the
 main acronymGIN/acronym data structure using the same bulk insert
 techniques used during initial index creation.  This greatly improves
 acronymGIN/acronym index update speed, even counting the additional
***
*** 812,829 
/varlistentry
  
varlistentry
!termxref linkend=guc-work-mem/term
 listitem
  para
   During a series of insertions into an existing acronymGIN/acronym
   index that has literalFASTUPDATE/ enabled, the system will clean up
   the pending-entry list whenever the list grows larger than
!  varnamework_mem/.  To avoid fluctuations in observed response time,
!  it's desirable to have pending-list cleanup occur in the background
!  (i.e., via autovacuum).  Foreground cleanup operations can be avoided by
!  increasing varnamework_mem/ or making autovacuum more aggressive.
!  However, enlarging varnamework_mem/ means that if a foreground
!  cleanup does occur, it will take even longer.
  /para
 /listitem
/varlistentry
--- 813,839 
/varlistentry
  
varlistentry
!termliteralPENDING_LIST_CLEANUP_SIZE/ and
!xref linkend=guc-work-mem/term
 listitem
  para
   During a series of insertions into an existing acronymGIN/acronym
   index that has literalFASTUPDATE/ enabled, the system will clean up
   the pending-entry list whenever the list grows larger than
!  literalPENDING_LIST_CLEANUP_SIZE/ (if not set, varnamework_mem/
!  is used as that threshold, instead). To avoid fluctuations in observed
!  response time, it's desirable to have pending-list cleanup occur in the
!  background (i.e., via autovacuum).  Foreground cleanup operations
!  can be avoided by increasing literalPENDING_LIST_CLEANUP_SIZE/
!  (or varnamework_mem/) or making autovacuum more aggressive.
!  However, enlarging the threshold of the cleanup operation means that
!  if a foreground cleanup does occur, it will take even longer.
! /para
! para
!  literalPENDING_LIST_CLEANUP_SIZE/ is an index storage parameter,
!  and allows each GIN index to have its own cleanup threshold.
!  For example, it's possible to increase the threshold only for the GIN
!  index which can be updated heavily, and decrease it otherwise.
  /para
 /listitem
/varlistentry
*** a/doc/src/sgml/ref/create_index.sgml
--- b/doc/src/sgml/ref/create_index.sgml
***
*** 356,361  CREATE [ UNIQUE ] INDEX [ CONCURRENTLY ] [ replaceable class=parametername/
--- 356,377 
  /listitem
 /varlistentry
 /variablelist
+variablelist
+varlistentry
+ termliteralPENDING_LIST_CLEANUP_SIZE//term
+ listitem
+ para
+  This setting specifies the maximum size 

Re: PENDING_LIST_CLEANUP_SIZE - maximum size of GIN pending list Re: [HACKERS] HEAD seems to generate larger WAL regarding GIN index

[Etsuro Fujita]

(2014/09/09 22:17), Fujii Masao wrote:

On Tue, Sep 9, 2014 at 1:28 AM, Jeff Janes jeff.ja...@gmail.com wrote:

I get some compiler warnings on v2 of this patch:

reloptions.c:219: warning: excess elements in struct initializer
reloptions.c:219: warning: (near initialization for 'intRelOpts[15]')



Attached is the updated version of the patch.


Thank you for updating the patch!

I took a quick review on the patch.  It looks good to me, but one thing 
I'm concerned about is


You wrote:
 The attached patch introduces the GIN index storage parameter
 PENDING_LIST_CLEANUP_SIZE which specifies the maximum size of
 GIN pending list. If it's not set, work_mem is used as that 
maximum size,

 instead. So this patch doesn't break the existing application which
 currently uses work_mem as the threshold of cleanup operation of
 the pending list. It has only not to set PENDING_LIST_CLEANUP_SIZE.

As you mentioned, I think it's important to consider for the existing 
applications, but I'm wondering if it would be a bit confusing users to 
have two parameters, PENDING_LIST_CLEANUP_SIZE and work_mem, for this 
setting.  Wouldn't it be easy-to-use to have only one parameter, 
PENDING_LIST_CLEANUP_SIZE?  How about setting PENDING_LIST_CLEANUP_SIZE 
to work_mem as the default value when running the CREATE INDEX command?


Sorry for the delay.

Best regards,
Etsuro Fujita


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Re: PENDING_LIST_CLEANUP_SIZE - maximum size of GIN pending list Re: [HACKERS] HEAD seems to generate larger WAL regarding GIN index

[Fujii Masao]

On Wed, Sep 10, 2014 at 12:15 PM, Etsuro Fujita
fujita.ets...@lab.ntt.co.jp wrote:
 (2014/09/09 22:17), Fujii Masao wrote:

 On Tue, Sep 9, 2014 at 1:28 AM, Jeff Janes jeff.ja...@gmail.com wrote:

 I get some compiler warnings on v2 of this patch:

 reloptions.c:219: warning: excess elements in struct initializer
 reloptions.c:219: warning: (near initialization for 'intRelOpts[15]')


 Attached is the updated version of the patch.


 Thank you for updating the patch!

 I took a quick review on the patch.  It looks good to me,

Thanks for reviewing the patch!

 but one thing I'm
 concerned about is

 You wrote:
 The attached patch introduces the GIN index storage parameter
 PENDING_LIST_CLEANUP_SIZE which specifies the maximum size of
 GIN pending list. If it's not set, work_mem is used as that maximum
 size,
 instead. So this patch doesn't break the existing application which
 currently uses work_mem as the threshold of cleanup operation of
 the pending list. It has only not to set PENDING_LIST_CLEANUP_SIZE.

 As you mentioned, I think it's important to consider for the existing
 applications, but I'm wondering if it would be a bit confusing users to have
 two parameters,

Yep.

 PENDING_LIST_CLEANUP_SIZE and work_mem, for this setting.
 Wouldn't it be easy-to-use to have only one parameter,
 PENDING_LIST_CLEANUP_SIZE?  How about setting PENDING_LIST_CLEANUP_SIZE to
 work_mem as the default value when running the CREATE INDEX command?

That's an idea. But there might be some users who want to change
the cleanup size per session like they can do by setting work_mem,
and your idea would prevent them from doing that...

So what about introduing pending_list_cleanup_size also as GUC?
That is, users can set the threshold by using either the reloption or
GUC.

 Sorry for the delay.

No problem. Thanks!

Regards,

-- 
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Re: PENDING_LIST_CLEANUP_SIZE - maximum size of GIN pending list Re: [HACKERS] HEAD seems to generate larger WAL regarding GIN index

[Jeff Janes]

On Sun, Aug 17, 2014 at 7:46 PM, Fujii Masao masao.fu...@gmail.com wrote:


 Thanks for reviewing the patch! ISTM that I failed to make the patch from
 my git repository... Attached is the rebased version.



I get some compiler warnings on v2 of this patch:

reloptions.c:219: warning: excess elements in struct initializer
reloptions.c:219: warning: (near initialization for 'intRelOpts[15]')


Cheers,

Jeff

Re: PENDING_LIST_CLEANUP_SIZE - maximum size of GIN pending list Re: [HACKERS] HEAD seems to generate larger WAL regarding GIN index

[Fujii Masao]

On Sat, Aug 16, 2014 at 4:23 PM, Sawada Masahiko sawada.m...@gmail.com wrote:
 On Fri, Aug 8, 2014 at 11:45 PM, Fujii Masao masao.fu...@gmail.com wrote:
 On Fri, Aug 8, 2014 at 11:43 PM, Fujii Masao masao.fu...@gmail.com wrote:
 On Mon, Apr 14, 2014 at 11:40 PM, Tom Lane t...@sss.pgh.pa.us wrote:
 Fujii Masao masao.fu...@gmail.com writes:
 On Tue, Apr 1, 2014 at 1:41 AM, Robert Haas robertmh...@gmail.com wrote:
 Should we try to install some hack around fastupdate for 9.4?  I fear
 the divergence between reasonable values of work_mem and reasonable
 sizes for that list is only going to continue to get bigger.  I'm sure
 there's somebody out there who has work_mem = 16GB, and stuff like
 263865a48973767ce8ed7b7788059a38a24a9f37 is only going to increase the
 appeal of large values.

 Controlling the threshold of the size of pending list only by GUC doesn't
 seem reasonable. Users may want to increase the threshold only for the
 GIN index which can be updated heavily, and decrease it otherwise. So
 I think that it's better to add new storage parameter for GIN index to 
 control
 the threshold, or both storage parameter and GUC.

 Yeah, -1 for a GUC.  A GIN-index-specific storage parameter seems more
 appropriate.

 The attached patch introduces the GIN index storage parameter
 PENDING_LIST_CLEANUP_SIZE which specifies the maximum size of
 GIN pending list. If it's not set, work_mem is used as that maximum size,
 instead. So this patch doesn't break the existing application which
 currently uses work_mem as the threshold of cleanup operation of
 the pending list. It has only not to set PENDING_LIST_CLEANUP_SIZE.

 This is an index storage parameter, and allows us to specify each
 threshold per GIN index. So, for example, we can increase the threshold
 only for the GIN index which can be updated heavily, and decrease it 
 otherwise.

 This patch uses another patch that I proposed (*1) as an infrastructure.
 Please apply that infrastructure patch first if you apply this patch.

 (*1)
 http://www.postgresql.org/message-id/CAHGQGwEanQ_e8WLHL25=bm_8z5zkyzw0k0yir+kdmv2hgne...@mail.gmail.com

 Regards,

 --
 Fujii Masao

 Sorry, I forgot to attached the patch This time, attached.


 I think that this patch should be rebased.
 It contains garbage code.

Thanks for reviewing the patch! ISTM that I failed to make the patch from
my git repository... Attached is the rebased version.

Regards,

-- 
Fujii Masao
diff --git a/doc/src/sgml/gin.sgml b/doc/src/sgml/gin.sgml
index 80a578d..24c8dc1 100644
--- a/doc/src/sgml/gin.sgml
+++ b/doc/src/sgml/gin.sgml
@@ -728,8 +728,9 @@
from the indexed item). As of productnamePostgreSQL/productname 8.4,
acronymGIN/ is capable of postponing much of this work by inserting
new tuples into a temporary, unsorted list of pending entries.
-   When the table is vacuumed, or if the pending list becomes too large
-   (larger than xref linkend=guc-work-mem), the entries are moved to the
+   When the table is vacuumed, or if the pending list becomes larger than
+   literalPENDING_LIST_CLEANUP_SIZE/literal (or
+   xref linkend=guc-work-mem if not set), the entries are moved to the
main acronymGIN/acronym data structure using the same bulk insert
techniques used during initial index creation.  This greatly improves
acronymGIN/acronym index update speed, even counting the additional
@@ -812,18 +813,27 @@
   /varlistentry
 
   varlistentry
-   termxref linkend=guc-work-mem/term
+   termliteralPENDING_LIST_CLEANUP_SIZE/ and
+   xref linkend=guc-work-mem/term
listitem
 para
  During a series of insertions into an existing acronymGIN/acronym
  index that has literalFASTUPDATE/ enabled, the system will clean up
  the pending-entry list whenever the list grows larger than
- varnamework_mem/.  To avoid fluctuations in observed response time,
- it's desirable to have pending-list cleanup occur in the background
- (i.e., via autovacuum).  Foreground cleanup operations can be avoided by
- increasing varnamework_mem/ or making autovacuum more aggressive.
- However, enlarging varnamework_mem/ means that if a foreground
- cleanup does occur, it will take even longer.
+ literalPENDING_LIST_CLEANUP_SIZE/ (if not set, varnamework_mem/
+ is used as that threshold, instead). To avoid fluctuations in observed
+ response time, it's desirable to have pending-list cleanup occur in the
+ background (i.e., via autovacuum).  Foreground cleanup operations
+ can be avoided by increasing literalPENDING_LIST_CLEANUP_SIZE/
+ (or varnamework_mem/) or making autovacuum more aggressive.
+ However, enlarging the threshold of the cleanup operation means that
+ if a foreground cleanup does occur, it will take even longer.
+/para
+para
+ literalPENDING_LIST_CLEANUP_SIZE/ is an index storage parameter,
+ and allows each GIN index to have its own cleanup threshold.
+ For example, it's possible to increase the 

Re: PENDING_LIST_CLEANUP_SIZE - maximum size of GIN pending list Re: [HACKERS] HEAD seems to generate larger WAL regarding GIN index

[Sawada Masahiko]

On Fri, Aug 8, 2014 at 11:45 PM, Fujii Masao masao.fu...@gmail.com wrote:
 On Fri, Aug 8, 2014 at 11:43 PM, Fujii Masao masao.fu...@gmail.com wrote:
 On Mon, Apr 14, 2014 at 11:40 PM, Tom Lane t...@sss.pgh.pa.us wrote:
 Fujii Masao masao.fu...@gmail.com writes:
 On Tue, Apr 1, 2014 at 1:41 AM, Robert Haas robertmh...@gmail.com wrote:
 Should we try to install some hack around fastupdate for 9.4?  I fear
 the divergence between reasonable values of work_mem and reasonable
 sizes for that list is only going to continue to get bigger.  I'm sure
 there's somebody out there who has work_mem = 16GB, and stuff like
 263865a48973767ce8ed7b7788059a38a24a9f37 is only going to increase the
 appeal of large values.

 Controlling the threshold of the size of pending list only by GUC doesn't
 seem reasonable. Users may want to increase the threshold only for the
 GIN index which can be updated heavily, and decrease it otherwise. So
 I think that it's better to add new storage parameter for GIN index to 
 control
 the threshold, or both storage parameter and GUC.

 Yeah, -1 for a GUC.  A GIN-index-specific storage parameter seems more
 appropriate.

 The attached patch introduces the GIN index storage parameter
 PENDING_LIST_CLEANUP_SIZE which specifies the maximum size of
 GIN pending list. If it's not set, work_mem is used as that maximum size,
 instead. So this patch doesn't break the existing application which
 currently uses work_mem as the threshold of cleanup operation of
 the pending list. It has only not to set PENDING_LIST_CLEANUP_SIZE.

 This is an index storage parameter, and allows us to specify each
 threshold per GIN index. So, for example, we can increase the threshold
 only for the GIN index which can be updated heavily, and decrease it 
 otherwise.

 This patch uses another patch that I proposed (*1) as an infrastructure.
 Please apply that infrastructure patch first if you apply this patch.

 (*1)
 http://www.postgresql.org/message-id/CAHGQGwEanQ_e8WLHL25=bm_8z5zkyzw0k0yir+kdmv2hgne...@mail.gmail.com

 Regards,

 --
 Fujii Masao

 Sorry, I forgot to attached the patch This time, attached.


I think that this patch should be rebased.
It contains garbage code.

Regards,

---
Sawada Masahiko


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PENDING_LIST_CLEANUP_SIZE - maximum size of GIN pending list Re: [HACKERS] HEAD seems to generate larger WAL regarding GIN index

[Fujii Masao]

On Mon, Apr 14, 2014 at 11:40 PM, Tom Lane t...@sss.pgh.pa.us wrote:
 Fujii Masao masao.fu...@gmail.com writes:
 On Tue, Apr 1, 2014 at 1:41 AM, Robert Haas robertmh...@gmail.com wrote:
 Should we try to install some hack around fastupdate for 9.4?  I fear
 the divergence between reasonable values of work_mem and reasonable
 sizes for that list is only going to continue to get bigger.  I'm sure
 there's somebody out there who has work_mem = 16GB, and stuff like
 263865a48973767ce8ed7b7788059a38a24a9f37 is only going to increase the
 appeal of large values.

 Controlling the threshold of the size of pending list only by GUC doesn't
 seem reasonable. Users may want to increase the threshold only for the
 GIN index which can be updated heavily, and decrease it otherwise. So
 I think that it's better to add new storage parameter for GIN index to 
 control
 the threshold, or both storage parameter and GUC.

 Yeah, -1 for a GUC.  A GIN-index-specific storage parameter seems more
 appropriate.

The attached patch introduces the GIN index storage parameter
PENDING_LIST_CLEANUP_SIZE which specifies the maximum size of
GIN pending list. If it's not set, work_mem is used as that maximum size,
instead. So this patch doesn't break the existing application which
currently uses work_mem as the threshold of cleanup operation of
the pending list. It has only not to set PENDING_LIST_CLEANUP_SIZE.

This is an index storage parameter, and allows us to specify each
threshold per GIN index. So, for example, we can increase the threshold
only for the GIN index which can be updated heavily, and decrease it otherwise.

This patch uses another patch that I proposed (*1) as an infrastructure.
Please apply that infrastructure patch first if you apply this patch.

(*1)
http://www.postgresql.org/message-id/CAHGQGwEanQ_e8WLHL25=bm_8z5zkyzw0k0yir+kdmv2hgne...@mail.gmail.com

Regards,

-- 
Fujii Masao


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Re: PENDING_LIST_CLEANUP_SIZE - maximum size of GIN pending list Re: [HACKERS] HEAD seems to generate larger WAL regarding GIN index

[Fujii Masao]

On Fri, Aug 8, 2014 at 11:43 PM, Fujii Masao masao.fu...@gmail.com wrote:
 On Mon, Apr 14, 2014 at 11:40 PM, Tom Lane t...@sss.pgh.pa.us wrote:
 Fujii Masao masao.fu...@gmail.com writes:
 On Tue, Apr 1, 2014 at 1:41 AM, Robert Haas robertmh...@gmail.com wrote:
 Should we try to install some hack around fastupdate for 9.4?  I fear
 the divergence between reasonable values of work_mem and reasonable
 sizes for that list is only going to continue to get bigger.  I'm sure
 there's somebody out there who has work_mem = 16GB, and stuff like
 263865a48973767ce8ed7b7788059a38a24a9f37 is only going to increase the
 appeal of large values.

 Controlling the threshold of the size of pending list only by GUC doesn't
 seem reasonable. Users may want to increase the threshold only for the
 GIN index which can be updated heavily, and decrease it otherwise. So
 I think that it's better to add new storage parameter for GIN index to 
 control
 the threshold, or both storage parameter and GUC.

 Yeah, -1 for a GUC.  A GIN-index-specific storage parameter seems more
 appropriate.

 The attached patch introduces the GIN index storage parameter
 PENDING_LIST_CLEANUP_SIZE which specifies the maximum size of
 GIN pending list. If it's not set, work_mem is used as that maximum size,
 instead. So this patch doesn't break the existing application which
 currently uses work_mem as the threshold of cleanup operation of
 the pending list. It has only not to set PENDING_LIST_CLEANUP_SIZE.

 This is an index storage parameter, and allows us to specify each
 threshold per GIN index. So, for example, we can increase the threshold
 only for the GIN index which can be updated heavily, and decrease it 
 otherwise.

 This patch uses another patch that I proposed (*1) as an infrastructure.
 Please apply that infrastructure patch first if you apply this patch.

 (*1)
 http://www.postgresql.org/message-id/CAHGQGwEanQ_e8WLHL25=bm_8z5zkyzw0k0yir+kdmv2hgne...@mail.gmail.com

 Regards,

 --
 Fujii Masao

Sorry, I forgot to attached the patch This time, attached.

Regards,

-- 
Fujii Masao
*** a/doc/src/sgml/gin.sgml
--- b/doc/src/sgml/gin.sgml
***
*** 728,735 
 from the indexed item). As of productnamePostgreSQL/productname 8.4,
 acronymGIN/ is capable of postponing much of this work by inserting
 new tuples into a temporary, unsorted list of pending entries.
!When the table is vacuumed, or if the pending list becomes too large
!(larger than xref linkend=guc-work-mem), the entries are moved to the
 main acronymGIN/acronym data structure using the same bulk insert
 techniques used during initial index creation.  This greatly improves
 acronymGIN/acronym index update speed, even counting the additional
--- 728,736 
 from the indexed item). As of productnamePostgreSQL/productname 8.4,
 acronymGIN/ is capable of postponing much of this work by inserting
 new tuples into a temporary, unsorted list of pending entries.
!When the table is vacuumed, or if the pending list becomes larger than
!literalPENDING_LIST_CLEANUP_SIZE/literal (or
!xref linkend=guc-work-mem if not set), the entries are moved to the
 main acronymGIN/acronym data structure using the same bulk insert
 techniques used during initial index creation.  This greatly improves
 acronymGIN/acronym index update speed, even counting the additional
***
*** 812,829 
/varlistentry
  
varlistentry
!termxref linkend=guc-work-mem/term
 listitem
  para
   During a series of insertions into an existing acronymGIN/acronym
   index that has literalFASTUPDATE/ enabled, the system will clean up
   the pending-entry list whenever the list grows larger than
!  varnamework_mem/.  To avoid fluctuations in observed response time,
!  it's desirable to have pending-list cleanup occur in the background
!  (i.e., via autovacuum).  Foreground cleanup operations can be avoided by
!  increasing varnamework_mem/ or making autovacuum more aggressive.
!  However, enlarging varnamework_mem/ means that if a foreground
!  cleanup does occur, it will take even longer.
  /para
 /listitem
/varlistentry
--- 813,839 
/varlistentry
  
varlistentry
!termliteralPENDING_LIST_CLEANUP_SIZE/ and
!xref linkend=guc-work-mem/term
 listitem
  para
   During a series of insertions into an existing acronymGIN/acronym
   index that has literalFASTUPDATE/ enabled, the system will clean up
   the pending-entry list whenever the list grows larger than
!  literalPENDING_LIST_CLEANUP_SIZE/ (if not set, varnamework_mem/
!  is used as that threshold, instead). To avoid fluctuations in observed
!  response time, it's desirable to have pending-list cleanup occur in the
!  background (i.e., via autovacuum).  Foreground cleanup operations
!  can be avoided by increasing literalPENDING_LIST_CLEANUP_SIZE/
!  (or 

Re: PENDING_LIST_CLEANUP_SIZE - maximum size of GIN pending list Re: [HACKERS] HEAD seems to generate larger WAL regarding GIN index

[Michael Paquier]

On Fri, Aug 8, 2014 at 11:43 PM, Fujii Masao masao.fu...@gmail.com wrote:
 The attached patch introduces...
A patch perhaps? :)
-- 
Michael


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