Re: Creating a function for exposing memory usage of backend process

Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>

From: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
To: Kasahara Tatsuhito <kasahara.tatsuhito@gmail.com>
Cc: Fujii Masao <masao.fujii@oss.nttdata.com>, torikoshia <torikoshia@oss.nttdata.com>, PostgreSQL-development <pgsql-hackers@postgresql.org>, Robert Haas <robertmhaas@gmail.com>
Date: 2020-06-26T06:42:31Z
Lists: pgsql-hackers
Hi,

While going through the mail chain on relation, plan and catalogue
caching [1], I'm thinking on the lines that is there a way to know the
current relation, plan and catalogue cache sizes? If there is a way
already,  please ignore this and it would be grateful if someone point
me to that.

Posting this here as I felt it's relevant.

If there is no such way to know the cache sizes and other info such as
statistics, number of entries, cache misses, hits etc.  can the
approach discussed here be applied?

If the user knows the cache statistics and other information, may be
we can allow user to take appropriate actions such as allowing him to
delete few entries through a command or some other way.

I'm sorry, If I'm diverting the topic being discussed in this mail
thread, please ignore if it is irrelevant.

[1] - https://www.postgresql.org/message-id/flat/20161219.201505.11562604.horiguchi.kyotaro%40lab.ntt.co.jp

With Regards,
Bharath Rupireddy.
EnterpriseDB: http://www.enterprisedb.com



Commits

  1. Add regression test for pg_backend_memory_contexts.

  2. Move codes for pg_backend_memory_contexts from mmgr/mcxt.c to adt/mcxtfuncs.c.

  3. Prevent non-superusers from reading pg_backend_memory_contexts, by default.

  4. Add pg_backend_memory_contexts system view.

  5. Fix yet another issue with step generation in partition pruning.