Re: Ext4 and the "30 second window of death"

From: Matthew Garrett
Date: Wed Apr 01 2009 - 17:26:29 EST


On Wed, Apr 01, 2009 at 02:21:43PM -0700, Ray Lee wrote:
> On Wed, Apr 1, 2009 at 10:43 AM, Matthew Garrett <mjg59@xxxxxxxxxxxxx> wrote:
> > I've got absolutely no idea why anyone would want fsync() to stop
> > meaning "Put my data on the disk please".
>
> Some guy named Andrew used to run a kernel with 'return 0' at the top
> of fsync and fdatasync: http://lkml.org/lkml/2007/4/27/88
>
> It's that the latency penalty of apps using *sync() on common hardware
> sucks. That's all, and finding a way to fix that would make this
> entire thread go away, I think.

And also disk spinups.
--
Matthew Garrett | mjg59@xxxxxxxxxxxxx
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