Re: High context switches occurring

Yes, it's turned on, unfortunately it got overlooked during the setup,
and until now...!

It's mostly a 'read' application, I increased the vm.max-readahead to
2048 from the default 256, after which I've not seen the CS storm,
though it could be incidental.

Thanks,
Anjan

-----Original Message-----
From: Scott Marlowe [mailto:smarlowe@g2switchworks.com]
Sent: Tuesday, November 22, 2005 3:38 PM
To: Anjan Dave
Cc: Tom Lane; Vivek Khera; Postgresql Performance
Subject: Re: [PERFORM] High context switches occurring

On Tue, 2005-11-22 at 14:33, Anjan Dave wrote:
> Is there any way to get a temporary relief from this Context Switching
> storm? Does restarting postmaster help?
>
> It seems that I can recreate the heavy CS with just one SELECT
> statement...and then when multiple such SELECT queries are coming in,
> things just get hosed up until we cancel a bunch of queries...

Is your machine a hyperthreaded one?  Some folks have found that turning
off hyper threading helps.  I knew it made my servers better behaved in
the past.