Re: SLRU statistics

Tom Lane <tgl@sss.pgh.pa.us>

From: Tom Lane <tgl@sss.pgh.pa.us>
To: Fujii Masao <masao.fujii@oss.nttdata.com>
Cc: Tomas Vondra <tomas.vondra@2ndquadrant.com>, Alvaro Herrera <alvherre@2ndquadrant.com>, Masahiko Sawada <masahiko.sawada@2ndquadrant.com>, "tsunakawa.takay@fujitsu.com" <tsunakawa.takay@fujitsu.com>, "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
Date: 2020-05-13T14:26:39Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →
  1. Fix async.c to not register any SLRU stats counts in the postmaster.

  2. Use proper GetDatum function in pg_stat_get_slru().

  3. Initialize SLRU stats entries to zero.

  4. Remove pg_xact from pg_stat_reset_slru docs

  5. Remove pg_xact entry from SLRU stats

  6. Track SLRU page hits in SimpleLruReadPage_ReadOnly

  7. Fix typo in SLRU stats documentation

  8. Collect statistics about SLRU caches

  9. Simplify and rename some GUC variables, per various recent discussions:

Fujii Masao <masao.fujii@oss.nttdata.com> writes:
> On 2020/05/13 17:21, Tomas Vondra wrote:
>> On Wed, May 13, 2020 at 04:10:30PM +0900, Fujii Masao wrote:
>>> Also I found another minor issue; SLRUStats has not been initialized to 0
>>> and which could update the counters unexpectedly. Attached patch fixes
>>> this issue.

> Pushed both. Thanks!

Why is that necessary?  A static variable is defined by C to start off
as zeroes.

			regards, tom lane