Re: [xfs] f876e446: +1.2% fileio.requests_per_sec

[Dave Chinner]

On Mon, Mar 03, 2014 at 10:21:51PM +0800, Fengguang Wu wrote:
> Hi Dave,
> 
> We noticed the below changes on commit f876e44603ad091c840a5fae5b0753bbb421c037
> ("xfs: always do log forces via the workqueue"):
> 
> Basically there are +1.2% increased throughput with +29.5% increased
> context switches.

Yes, the increase in context switches is expected. Every sync IO
causes a log force if it changed inode metadata, and the above
commit, as it describes, moves them to a work queue. Hence there's
more context switches involved in a log force that has to do work.

Cheers,

Dave.
-- 
Dave Chinner
david@xxxxxxxxxxxxx
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