From: | Rémy Beaumont <remyb(at)medrium(dot)com> |
---|---|
To: | josh(at)agliodbs(dot)com |
Cc: | pgsql-performance(at)postgresql(dot)org |
Subject: | Re: High load and iowait but no disk access |
Date: | 2005-08-30 18:42:38 |
Message-ID: | 22924e579ad7e7e0deb5133eb905618b@medrium.com |
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Thread: | |
Lists: | pgsql-performance |
On 30-Aug-05, at 14:32, Josh Berkus wrote:
> Remy,
>
>> The behavior we see is that when running queries that do random reads
>> on disk, IOWAIT goes over 80% and actual disk IO falls to a crawl at a
>> throughput bellow 3000kB/s (We usually average 40000 kB/s to 80000
>> kB/s
>> on sequential read operations on the netapps)
>
> This seems pretty low for a NetApp -- you should be able to manage up
> to
> 180mb/s, if not higher. Are you sure it's configured correctly?
Hi Josh,
The config has been reviewed by NetApp. We do get rates higher then
80mb/s, but on average, that's what we get.
Do you have NetApp filers deployed ?
How many spindles do you have in your volume ?
On which OS are you running Postgres ?
Thanks,
Rémy
>
> --
> --Josh
>
> Josh Berkus
> Aglio Database Solutions
> San Francisco
>
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