Re: Database performs massive reads when I'm doing writes.

----- Original Message -----

> From: "Jeff Janes" <jeff(dot)janes(at)gmail(dot)com>
> To: "Ray Cote" <rgacote(at)appropriatesolutions(dot)com>
> Cc: pgsql-general(at)postgresql(dot)org
> Sent: Thursday, June 6, 2013 5:41:00 PM
> Subject: Re: [GENERAL] Database performs massive reads when I'm doing
> writes.

> On Thu, Jun 6, 2013 at 2:12 PM, Ray Cote <
> rgacote(at)appropriatesolutions(dot)com > wrote:

> > It is Postmaster itself:
>
> > 11068 - 315.9M 136K 0K 85% postmaster
>
> > 11000 - 56808K 8K 0K 15% postmaster
>
> > 11003 - 0K 80K 0K 0% postmaster
>
> > 11004 - 0K 24K 0K 0% postmaster
>
> > 11067 - 0K 0K 0K 0% load_rets.py
>

> > The above are the atop lines for just postmaster. This is a 10s
> > snapshot so you can see lots of read activity.
>
> > The load_rets.py task is the Python script loading the database.
>

> The postmaster has many children, each of which is responsible for
> something different. If you display the full command line rather
> than just the abbreviated one, it will give you more info on exactly
> which child is using the disk, for example:

> PID DSK COMMAND-LINE

> 3950 16% postgres: jjanes jjanes [local] UPDATE
> 2978 0% postgres: checkpointer process

> 2982 0% postgres: stats collector process

> Cheers,

> Jeff
Hi Jeff:

I can see that now after pressing c in disk display mode:
19007 - D 86% postgres: postgres petersons 127.0.0.1(59702) UPDATE
11003 - S 12% postgres: writer process
11004 - S 2% postgres: wal writer process

This is how it looks when running properly (doing a big update at the moment).
Thanks for the lead. Learning much about atop today.
--Ray

--

Ray Cote, President Appropriate Solutions, Inc.
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