pg.ddx.io  pgsql-performance@postgresql.org mailing list archive  

help / color / mirror / Atom feed
From: Mark Kirkwood <mark.kirkwood@catalyst.net.nz>
To: Josh Berkus <josh@agliodbs.com>
Cc: Scott Marlowe <scott.marlowe@gmail.com>
Cc: postgres performance list <pgsql-performance@postgresql.org>
Subject: Re: High CPU usage / load average after upgrading to Ubuntu 12.04
Date: Tue, 19 Feb 2013 17:28:00 +1300
Message-ID: <5122FF50.8030903@catalyst.net.nz> (raw)
In-Reply-To: <5122C9D9.9040909@agliodbs.com>
References: <60B572D9298D944580F7D51195DD30804357FA4ABF@VMBX125.ihostexchange.net>
	<CABdoJnZmO3M3a20KZWDpfaLG++deaHPdGY8AMPKfRF4Sz=GygQ@mail.gmail.com>
	<60B572D9298D944580F7D51195DD30804357FA4B60@VMBX125.ihostexchange.net>
	<dpg5ol29ltnb072ngdg8auj4.1360707457411@email.android.com>
	<60B572D9298D944580F7D51195DD30804357FA4C11@VMBX125.ihostexchange.net>
	<511BE879.8080706@agliodbs.com>
	<511C2F10.3080409@agliodbs.com>
	<60B572D9298D944580F7D51195DD30804357FA4DE2@VMBX125.ihostexchange.net>
	<511D2F11.6040706@agliodbs.com>
	<60B572D9298D944580F7D51195DD308043580CAA0B@VMBX125.ihostexchange.net>
	<511D79FE.7060705@agliodbs.com>
	<60B572D9298D944580F7D51195DD308043580CAA87@VMBX125.ihostexchange.net>
	<CAOR=d=3CqRL5jrFRTSg9kFdcJzKpx3TJSsoDwRqpPUO=ENoFRQ@mail.gmail.com>
	<511E7DC0.4090506@agliodbs.com>
	<CAOR=d=2cEi=ibGS4DCrFAWq8VtCz6XEYDsMyarBX=evshLWgKg@mail.gmail.com>
	<5122C507.7060303@agliodbs.com>
	<CAOR=d=3bXmMmTvh3cKCizhwsijxg6wh6ADC053w-dbkC3e_zCQ@mail.gmail.com>
	<5122C9D9.9040909@agliodb s.com>
List-Unsubscribe:  <mailto:majordomo@postgresql.org?body=unsub%20pgsql-performance>

On 19/02/13 13:39, Josh Berkus wrote:
> Scott,
>
>> So do you have generally slow IO, or is it fsync behavior etc?
> All tests except pgBench show this system as superfast.  Bonnie++ and DD
> tests are good (200 to 300mb/s), and test_fsync shows 14K/second.
> Basically it has no issues until checkpoint kicks in, at which time the
> entire system basically halts for the duration of the checkpoint.
>
> For that matter, if I run a pgbench and halt it just before checkpoint
> kicks in, I get around 12000TPS, which is what I'd expect on this system.
>
> At this point, we've tried 3.2.0.26, 3.2.0.27, 3.4.0, and tried updating
> the RAID driver, and changing the IO scheduler.  Nothing seems to affect
> the behavior.   Testing using Ext4 (instead of XFS) next.
>
>

Might be worth looking at your vm.dirty_ratio, vm.dirty_background_ratio 
and friends settings. We managed to choke up a system with 16x SSD by 
leaving them at their defaults...

Cheers

Mark




-- 
Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-performance



view thread (33+ messages)  latest in thread

Message-ID: <5122FF50.8030903@catalyst.net.nz>
Permalink:  ../5122FF50.8030903@catalyst.net.nz/
Also on:    postgresql.org/message-id/5122FF50.8030903@catalyst.net.nz

 · 

reply
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-performance@postgresql.org
  Cc: mark.kirkwood@catalyst.net.nz, josh@agliodbs.com, scott.marlowe@gmail.com
  Subject: Re: High CPU usage / load average after upgrading to Ubuntu 12.04
  In-Reply-To: <5122FF50.8030903@catalyst.net.nz>

* 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