Messages in this thread | | | Date | Fri, 20 Aug 2010 13:56:21 +0800 | From | Wu Fengguang <> | Subject | Re: [PATCH] writeback: remove the internal 5% low bound on dirty_ratio |
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On Fri, Aug 20, 2010 at 01:50:54PM +0800, Con Kolivas wrote: > On Fri, 20 Aug 2010 02:13:25 pm KOSAKI Motohiro wrote: > > > The dirty_ratio was silently limited to >= 5%. This is not a user > > > expected behavior. Let's rip it. > > > > > > It's not likely the user space will depend on the old behavior. > > > So the risk of breaking user space is very low. > > > > > > CC: Jan Kara <jack@suse.cz> > > > CC: Neil Brown <neilb@suse.de> > > > Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> > > > > Thank you. > > Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> > > I have tried to do this in the past, and setting this value to 0 on some > machines caused the machine to come to a complete standstill with small > writes to disk. It seemed there was some kind of "minimum" amount of data > required by the VM before anything would make it to the disk and I never > quite found out where that blockade occurred. This was some time ago (3 years > ago) so I'm not sure if the problem has since been fixed in the VM since > then. I suggest you do some testing with this value set to zero before > approving this change.
Good point. I'll do more homework. Thanks for the reminding!
Thanks, Fengguang
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