Here's one cook article on using pg_buffercache...
https://www.keithf4.com/a-large-database-does-not-mean-large-shared_buffers/
Regards,
Michael Vitale
Justin Pryzby <mailto:pry...@telsasoft.com>
Tuesday, March 12, 2019 4:11 PM
I've tuned ~40 postgres instances, primarily using log_checkpoints and
pg_stat_bgwriter, with custom RRD graphs. pg_buffercache does provide some
valuable insights, and I know it's commonly suggested to check
histogram of
usagecounts, but I've never had any idea how to apply that to tune
shared_buffers.
Could you elaborate on what procedure you suggest ?
Justin
MichaelDBA <mailto:michael...@sqlexec.com>
Tuesday, March 12, 2019 4:03 PM
Set shared_buffers more accurately by using pg_buffercache extension
and the related queries during high load times.
Regards,
Michael Vitale
Michael Lewis <mailto:mle...@entrata.com>
Tuesday, March 12, 2019 3:23 PM
On Tue, Mar 12, 2019 at 2:29 AM Laurenz Albe <laurenz.a...@cybertec.at
<mailto:laurenz.a...@cybertec.at>> wrote:
Daulat Ram wrote:
> I want to know about the working and importance of
shared_buffers in Postgresql?
> is it similar to the oracle database buffer cache?
Yes, exactly.
The main difference is that PostgreSQL uses buffered I/O, while
Oracle usually
uses direct I/O.
Usually you start with shared_buffers being the minimum of a
quarter of the
available RAM and 8 GB.
Any good rule of thumb or write up about when shared buffers in excess
of 8GBs makes sense (assuming system ram 64+ GBs perhaps)?
