From: Scott Ribe <scott_ribe@elevated-dev.com>
To: Kenny Bachman <kenny.bachman17@gmail.com>
Cc: pgsql-admin <pgsql-admin@lists.postgresql.org>
Subject: Re: Postgresql 14 performance
Date: Sun, 21 Aug 2022 12:57:54 -0600
Message-ID: <3FA5ECDA-A99E-4ACC-B431-54A5BC7FC4D4@elevated-dev.com> (raw)
In-Reply-To: <CAC0w7L+ezaB8tw-kh6rZC0RhG8ZwhLG_EkUErGEiUQ=f8uAC6g@mail.gmail.com>
References: <CAC0w7LL+uFgPvctiHMxrVZV-DnNVg2K_wFaeZwM96XQFkjk1uA@mail.gmail.com>
<62c9a8d8-8c0f-3c11-5cca-e05e126c25d8@gmail.com>
<CAC0w7L+ezaB8tw-kh6rZC0RhG8ZwhLG_EkUErGEiUQ=f8uAC6g@mail.gmail.com>
> On Aug 21, 2022, at 12:55 PM, Kenny Bachman <kenny.bachman17@gmail.com> wrote:
>
> How can we explain the cache doesn't work as expected? I mean, I expect more performant the second or third time running because of the cache. However, every time I run it I get the same exec time value.
Take a look at system paging activity, and at pg IO waits. (For the latter, I think you have to enable tracking in postgresql.conf.) Also take a peek at CPU usage--if cache is doing what you expect here, then CPU should go to 100% on one or more cores.
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To: pgsql-admin@postgresql.org
Cc: scott_ribe@elevated-dev.com, kenny.bachman17@gmail.com, pgsql-admin@lists.postgresql.org
Subject: Re: Postgresql 14 performance
In-Reply-To: <3FA5ECDA-A99E-4ACC-B431-54A5BC7FC4D4@elevated-dev.com>
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