Re: list of flags that pg_settings_get_flags reports
On Wed, Jul 20, 2022 at 01:51:36PM +0900, Fujii Masao wrote: > Attached is the updated version of the patch. It separates the list > for GUC flags from the table entry for pg_settings_get_flags() and > adds the table for it at the bottom of the existing function table. Thanks a lot for sending a patch. This looks fine to me. -- Michael signature.asc Description: PGP signature
Re: list of flags that pg_settings_get_flags reports
Hello On 2022-Jul-20, Fujii Masao wrote: > Attached is the updated version of the patch. It separates the list > for GUC flags from the table entry for pg_settings_get_flags() and > adds the table for it at the bottom of the existing function table. I lament the fact that the version of DocBook we use doesn't let us add captions; it would be much better to have "Flags to use with function pg_settings_get_flags()" under the table; unadorned, you have to guess or search. But that's already a problem with the other similar tables, so let's just plow ahead. +1 to this patch. -- Álvaro Herrera 48°01'N 7°57'E — https://www.EnterpriseDB.com/
huge_page_size parameter description in the pg 14 docs is not exact
https://www.postgresql.org/docs/15/runtime-config-resource.html#GUC-HUGE-PAGE-SIZE the following is from the above website: Some commonly available page sizes on modern 64 bit server architectures include: 2MB and 1GB (Intel and AMD), 16MB and 16GB (IBM POWER), and 64kB, 2MB, 32MB and 1GB (ARM). For more information about usage and support, but after my test, I found that: in the RHEL7.9(kernel version 3.10.0-1160),when I set the non default huge page size for huge_page_size parameter ,PG14 can not start； in the RHEL8.5(kernel version 4.18.0-348),when I set the non default huge page size for huge_page_size parameter ,PG14 can start 。 so , I think that: the huge_page_size parameter description in the PostgreSQL 14 documents is not exact. I suggest that : Some one should modify the postgreSQL 14 documents（https://www.postgresql.org/docs/15/runtime-config-resource.html#GUC-HUGE-PAGE-SIZE） like the following: in the RHEL7.x (kernel version 3.10.0-xxx), huge_page_size parameter can not set to the non default huge page size.
Re: huge_page_size parameter description in the pg 14 docs is not exact
On Wed, Jul 20, 2022 at 09:56:37PM +0800, yanliang lei wrote: > > https://www.postgresql.org/docs/15/runtime-config-resource.html# > GUC-HUGE-PAGE-SIZE > > > the following is from the above website: > > Some commonly available page sizes on modern 64 bit server architectures > include: > > 2MB and 1GB (Intel and AMD), 16MB and 16GB (IBM POWER), and 64kB, 2MB, 32MB > and > 1GB (ARM). For more information about usage and support, I think these are the sizes the CPUs support, no necessarily the ones that the operating system supports. > but after my test, I found that: > > in the RHEL7.9(kernel version 3.10.0-1160),when I set the non default huge > page > size for huge_page_size parameter ,PG14 can not start； > > in the RHEL8.5(kernel version 4.18.0-348),when I set the non default huge page > size for huge_page_size parameter ,PG14 can start 。 The paragraph begins with: Some commonly available page sizes on modern 64 bit server architectures include: which seems sufficient to suggest that all listed sizes might not be supported on all operating systems, and this is only supported on Linux, as documented. -- Bruce Momjian https://momjian.us EDB https://enterprisedb.com Indecision is a decision. Inaction is an action. Mark Batterson
Re: list of flags that pg_settings_get_flags reports
On 2022/07/20 16:26, Michael Paquier wrote: On Wed, Jul 20, 2022 at 01:51:36PM +0900, Fujii Masao wrote: Attached is the updated version of the patch. It separates the list for GUC flags from the table entry for pg_settings_get_flags() and adds the table for it at the bottom of the existing function table. Thanks a lot for sending a patch. This looks fine to me. Pushed. Thanks! Regards, -- Fujii Masao Advanced Computing Technology Center Research and Development Headquarters NTT DATA CORPORATION
Re: list of flags that pg_settings_get_flags reports
On 2022/07/20 18:07, Alvaro Herrera wrote: Hello On 2022-Jul-20, Fujii Masao wrote: Attached is the updated version of the patch. It separates the list for GUC flags from the table entry for pg_settings_get_flags() and adds the table for it at the bottom of the existing function table. I lament the fact that the version of DocBook we use doesn't let us add captions; it would be much better to have "Flags to use with function pg_settings_get_flags()" under the table; unadorned, you have to guess or search. Or, though it's not a caption under the table, it's better to have "Flags to use with function pg_settings_get_flags()" in the title of the table as follows? - GUC Flags + GUC Flags To Use With Function pg_settings_get_flags() Regards, -- Fujii Masao Advanced Computing Technology Center Research and Development Headquarters NTT DATA CORPORATION
Re: huge_page_size parameter description in the pg 14 docs is not exact
On Thu, Jul 21, 2022 at 2:03 AM Bruce Momjian wrote: > On Wed, Jul 20, 2022 at 09:56:37PM +0800, yanliang lei wrote: > > https://www.postgresql.org/docs/15/runtime-config-resource.html# > > GUC-HUGE-PAGE-SIZE > > > > the following is from the above website: > > > > Some commonly available page sizes on modern 64 bit server architectures > > include: > > > > 2MB and 1GB (Intel and AMD), 16MB and 16GB (IBM POWER), and 64kB, 2MB, 32MB > > and > > 1GB (ARM). For more information about usage and support, > > I think these are the sizes the CPUs support, no necessarily the ones > that the operating system supports. Yeah, that's just some sizes that the architecture *might* support. Some eg laptop x86 chips might not have 1GB pages. You could look at the output of the cpuid program on Linux, or find similar info in dmesg etc. Then you need to tell the kernel to make some pages available. This message has some info from my testing of huge_page_size: https://www.postgresql.org/message-id/CA%2BhUKG%2BgdWThHi0v6TmiLgUE_rqqQ%2BPKw2t%2BkT6w08H36qzxpw%40mail.gmail.com
