The offending SELECT query that invoked the CS storm was optimized by
folks here last night, so it's hard to say if the VM setting made a
difference. I'll give it a try anyway.
Thanks,
Anjan
-----Original Message-----
From: Simon Riggs [mailto:simon@2ndquadrant.com]
Sent: Wednesday, November 23, 2005 1:14 PM
To: Anjan Dave
Cc: Scott Marlowe; Tom Lane; Vivek Khera; Postgresql Performance
Subject: Re: [PERFORM] High context switches occurring
On Tue, 2005-11-22 at 18:17 -0500, Anjan Dave wrote:
> 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.
Can you verify this, please?
Turn it back down again, try the test, then reset and try the test.
If that is a repeatable way of recreating one manifestation of the
problem then we will be further ahead than we are now.
Thanks,
Best Regards, Simon Riggs