From: Tom Lane <tgl@sss.pgh.pa.us>
To: Dennis Brouwer <dennis.brouwer@m4n.nl>
Cc: pgsql-admin@postgresql.org
Subject: Re: CPU causes 100% load in user space when ntp client runs and postgresql is under heavy load
Date: Tue, 25 Sep 2012 11:57:36 -0400
Message-ID: <21048.1348588656@sss.pgh.pa.us> (raw)
In-Reply-To: <CAMfP6GYjvsbYsqhs4YbYmyBw5TK8uOh8yzvcfTA2rh1_oQZP5w@mail.gmail.com>
References: <CAMfP6GYL4Tkga5MKO9=KR5n9Ht_4Nk3Qk4_K0g8Yug09FoJo7g@mail.gmail.com>
<16883.1348504245@sss.pgh.pa.us>
<CAMfP6GYjvsbYsqhs4YbYmyBw5TK8uOh8yzvcfTA2rh1_oQZP5w@mail.gmail.com>
Dennis Brouwer <dennis.brouwer@m4n.nl> writes:
> I now have excluded ntp as root cause for the CPU cycles being wasted in
> user space.
Good, cause that wasn't making any sense at all.
> I installed perf and monitored two servers (with different postgresql
> versions and hardware specification) which are "hanging" and have some
> output. Since I'm no die-hard at interpreting the output of perf top what
> would be the next step to do?
I'd suggest asking for help in pgsql-performance. I don't know much
about perf either (still an oprofile guy), but the people who do know
it hang out there.
regards, tom lane
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-admin@postgresql.org
Cc: tgl@sss.pgh.pa.us, dennis.brouwer@m4n.nl
Subject: Re: CPU causes 100% load in user space when ntp client runs and postgresql is under heavy load
In-Reply-To: <21048.1348588656@sss.pgh.pa.us>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox