Re: [DOCS] "managing kernel resources" and platform-specific notes
Alvaro Herrera writes: > We've got some platform-specific notes in the "managing kernel > resources" (17.4.1 on 8.4devel) page. Since we recently got > platform-specific sections in the installation instructions (15.8), it > seems a good idea to move these notes to the new sections. > Opinions? Hmm, I'm not convinced. 95% of what was put into 15.8 is really platform-specific *build* instructions. Merging configuration information into that doesn't seem appropriate. In general I think chapter 15 is about getting a correct set of binaries, while chapter 17 deals with system configuration issues. These should be kept separate, because in the common case of using a prepackaged build, chapter 15 is of no interest but 17 still is. It's quite likely that some of the stuff extracted from the old platform FAQs really belongs in 17. regards, tom lane -- Sent via pgsql-docs mailing list ([email protected]) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-docs
Re: [DOCS] "managing kernel resources" and platform-specific notes
Alvaro Herrera wrote: We've got some platform-specific notes in the "managing kernel resources" (17.4.1 on 8.4devel) page. Since we recently got platform-specific sections in the installation instructions (15.8), it seems a good idea to move these notes to the new sections. It was my intent to make 15.8 platform-specific *installation* notes. Platform-specific run time and configuration notes should be kept close to where those issues are discussed, IMO. -- Sent via pgsql-docs mailing list ([email protected]) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-docs
Re: [DOCS] [ADMIN] shared_buffers and shmmax
Bruce Momjian wrote: > OK, I never got the change applied because of Alvaro's objection so > there is nothing to revert. Alvaro said he has an idea for improved > wording; I do not. I think we should add a more explicit note, like in the attached patch. -- Alvaro Herrerahttp://www.CommandPrompt.com/ The PostgreSQL Company - Command Prompt, Inc. Index: runtime.sgml === RCS file: /home/alvherre/Code/cvs/pgsql/doc/src/sgml/runtime.sgml,v retrieving revision 1.422 diff -c -p -r1.422 runtime.sgml *** runtime.sgml 20 Nov 2008 11:48:26 - 1.422 --- runtime.sgml 16 Dec 2008 14:40:42 - *** set semsys:seminfo_semmsl=32 *** 1124,1129 --- 1124,1139 + + + + The multipliers for shared_buffers and + wal_buffers should be the number of buffers, not the + amount in bytes. To find out the number of shared or wal buffers, divide + the amount in bytes by and + , respectively. + + -- Sent via pgsql-docs mailing list ([email protected]) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-docs
[DOCS] "managing kernel resources" and platform-specific notes
Hi, We've got some platform-specific notes in the "managing kernel resources" (17.4.1 on 8.4devel) page. Since we recently got platform-specific sections in the installation instructions (15.8), it seems a good idea to move these notes to the new sections. Opinions? -- Alvaro Herrerahttp://www.CommandPrompt.com/ The PostgreSQL Company - Command Prompt, Inc. -- Sent via pgsql-docs mailing list ([email protected]) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-docs
Re: [DOCS] [ADMIN] shared_buffers and shmmax
Alvaro Herrera wrote: > Bruce Momjian wrote: > > > OK, I never got the change applied because of Alvaro's objection so > > there is nothing to revert. Alvaro said he has an idea for improved > > wording; I do not. > > I think we should add a more explicit note, like in the attached patch. Committed. Bruce told me on IM he still wants to do more changes. -- Alvaro Herrerahttp://www.CommandPrompt.com/ The PostgreSQL Company - Command Prompt, Inc. -- Sent via pgsql-docs mailing list ([email protected]) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-docs
Re: [DOCS] [ADMIN] shared_buffers and shmmax
Alvaro Herrera wrote: > Alvaro Herrera wrote: > > Bruce Momjian wrote: > > > > > OK, I never got the change applied because of Alvaro's objection so > > > there is nothing to revert. Alvaro said he has an idea for improved > > > wording; I do not. > > > > I think we should add a more explicit note, like in the attached patch. > > Committed. Bruce told me on IM he still wants to do more changes. > > -- > Alvaro Herrerahttp://www.CommandPrompt.com/ > The PostgreSQL Company - Command Prompt, Inc. OK, updated patch. I added item descriptions and removed Alvaro's paragraph; I worked with Alvaro on this patch. You can see the output in table 17-2: http://momjian.us/tmp/pgsql/kernel-resources.html -- Bruce Momjian http://momjian.us EnterpriseDB http://enterprisedb.com + If your life is a hard drive, Christ can be your backup. + Index: doc/src/sgml/runtime.sgml === RCS file: /cvsroot/pgsql/doc/src/sgml/runtime.sgml,v retrieving revision 1.423 diff -c -c -r1.423 runtime.sgml *** doc/src/sgml/runtime.sgml 16 Dec 2008 19:30:43 - 1.423 --- doc/src/sgml/runtime.sgml 16 Dec 2008 22:01:14 - *** *** 1087,1141 Name !Approximate multiplier (bytes per increment) as of 8.3 !1800 + 270 * !1800 + 270 * !770 + 270 * !8400 (assuming 8 kB BLCKSZ) !8200 (assuming 8 kB XLOG_BLCKSZ) Fixed space requirements !770 kB ! ! ! The multipliers for shared_buffers and ! wal_buffers should be the number of buffers, not the ! amount in bytes. To find out the number of shared or wal buffers, divide ! the amount in bytes by and ! , respectively. ! ! ! ! Resource Limits --- 1087,1137 Name !Shared memory requirements, as of 8.3 !1800 + 270 * bytes per connection !1800 + 270 * bytes per worker !770 + 270 * bytes per prepared transaction ! + 208 bytes per shared buffer ! + 8 bytes per WAL buffer Fixed space requirements !770k bytes ! ! These shared memory allocations are reserved at database server ! start and remain static. ! Resource Limits -- Sent via pgsql-docs mailing list ([email protected]) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-docs
Re: [DOCS] [ADMIN] shared_buffers and shmmax
Bruce Momjian writes: > OK, updated patch. I added item descriptions and removed Alvaro's > paragraph; I worked with Alvaro on this patch. This still seems pretty misleading, as for example > > > > !1800 + 270 * !linkend="guc-max-locks-per-transaction"> bytes per connection > sounds like it might mean bytes per *active* connection, when of course the correct way to figure it is by multiplying by max_connections. If you're going to give a formula, why not just give a formula, eg (1800 + 270 * max_locks_per_transaction) * (max_connections + autovacuum_max_workers) regards, tom lane -- Sent via pgsql-docs mailing list ([email protected]) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-docs
Re: [DOCS] [ADMIN] shared_buffers and shmmax
Tom Lane wrote: > Bruce Momjian writes: > > OK, updated patch. I added item descriptions and removed Alvaro's > > paragraph; I worked with Alvaro on this patch. > > This still seems pretty misleading, as for example > > > > > > > > > !1800 + 270 * > !linkend="guc-max-locks-per-transaction"> bytes per > > connection > > > > sounds like it might mean bytes per *active* connection, when of course > the correct way to figure it is by multiplying by max_connections. > If you're going to give a formula, why not just give a formula, eg > > (1800 + 270 * max_locks_per_transaction) * (max_connections + > autovacuum_max_workers) > > regards, tom lane You mean like this: http://momjian.us/tmp/pgsql/kernel-resources.html -- Bruce Momjian http://momjian.us EnterpriseDB http://enterprisedb.com + If your life is a hard drive, Christ can be your backup. + Index: doc/src/sgml/runtime.sgml === RCS file: /cvsroot/pgsql/doc/src/sgml/runtime.sgml,v retrieving revision 1.423 diff -c -c -r1.423 runtime.sgml *** doc/src/sgml/runtime.sgml 16 Dec 2008 19:30:43 - 1.423 --- doc/src/sgml/runtime.sgml 17 Dec 2008 01:30:21 - *** *** 1087,1141 Name !Approximate multiplier (bytes per increment) as of 8.3 ! !1800 + 270 * ! ! ! ! !1800 + 270 * !770 + 270 * !8400 (assuming 8 kB BLCKSZ) !8200 (assuming 8 kB XLOG_BLCKSZ) Fixed space requirements !770 kB ! ! ! The multipliers for shared_buffers and ! wal_buffers should be the number of buffers, not the ! amount in bytes. To find out the number of shared or wal buffers, divide ! the amount in bytes by and ! , respectively. ! ! ! ! Resource Limits --- 1087,1132 Name !Shared memory bytes required, as of 8.3 !, !(1800 + 270 * ) * ( + ) !(770 + 270 * ) * !( + 208) * !( + 8) * Fixed space requirements !770k bytes ! ! These shared memory allocations are reserved at database server ! start and remain static. ! Resource Limits -- Sent via pgsql-docs mailing list ([email protected]) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-docs
Re: [DOCS] [ADMIN] shared_buffers and shmmax
Bruce Momjian writes: > Tom Lane wrote: >> If you're going to give a formula, why not just give a formula, eg > You mean like this: > http://momjian.us/tmp/pgsql/kernel-resources.html Yeah, more or less. A couple thoughts now that I see it worked out: * Combining the entries for max_connections and autovacuum_max_workers is probably just making it look more complicated than it needs to. How about two rows that just happen to have similar formulas, viz max_connections (1800 + 270 * max_locks_per_transaction) * max_connections autovacuum_max_workers (1800 + 270 * max_locks_per_transaction) * autovacuum_max_workers * The right-hand column header should be something like "Approximate shared memory bytes..." to avoid the impression that these formulas are meant to be exact. * If we do it like this then the left-hand column is really redundant, not to say wrong because the right-hand formulas depend on more than the single variable mentioned. How about something like Table 17-2 PostgreSQL shared memory usage Purpose Approximate number of bytes required (as of 8.3) Per-connection state(1800 + 270 * max_locks_per_transaction) * max_connections Autovacuum worker state (1800 + 270 * max_locks_per_transaction) * autovacuum_max_workers Prepared transaction state ... Shared disk buffers ... WAL buffers ... Fixed space requirements770kB regards, tom lane -- Sent via pgsql-docs mailing list ([email protected]) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-docs
