Hi Ilya,
I mount the esx4 file system with: nofail,noatime,nodiratime,nobarrier,commit=1
The esxt3 file system for the log is mounted with: nofail,noatime,nodiratime,data=writeback
Attached is a tar file with charts from last night's runs. File 0_dirty_background_bytes.htm has the default with
dirty_background_bytes=0and dirty_background_ratio=10 (it's a warm-up run, so it starts with low throughput and a high
readrate). I still see a little bit of burstiness with dirty_background_bytes=50MB, but no burstiness with
dirty_background_ratiofrom 10MB down to even 1MB.
Thanks everyone for the advice,
Reza
> -----Original Message-----
> From: Ilya Kosmodemiansky [mailto:ilya.kosmodemiansky@postgresql-
> consulting.com]
> Sent: Thursday, April 03, 2014 11:12 PM
> To: Reza Taheri
> Cc: Heikki Linnakangas; pgsql-performance@postgresql.org
> Subject: Re: [PERFORM] PGSQL, checkpoints, and file system syncs
>
> Hi Reza,
>
> vm.dirty_bytes indeed makes sense, but just in case: how exactly is your
> ext4 mount? Particularly, have you disabled barrier?
>
> Ilya
>
> On Thu, Apr 3, 2014 at 8:11 PM, Reza Taheri <rtaheri@vmware.com> wrote:
> >> Try setting the vm.dirty_bytes sysctl. Something like 256MB might be
> >> a good starting point.
>
>
>
> --
> Ilya Kosmodemiansky,
>
> PostgreSQL-Consulting.com
> tel. +14084142500
> cell. +4915144336040
> ik@postgresql-consulting.com
