Messages in this thread | | | Date | Mon, 28 Sep 2009 16:38:11 +0900 (JST) | Subject | Re: IO scheduler based IO controller V10 | From | Ryo Tsuruta <> |
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Hi Rik,
Rik van Riel <riel@redhat.com> wrote: > Ryo Tsuruta wrote: > > > Because dm-ioband provides faireness in terms of how many IO requests > > are issued or how many bytes are transferred, so this behaviour is to > > be expected. Do you think fairness in terms of IO requests and size is > > not fair? > > When there are two workloads competing for the same > resources, I would expect each of the workloads to > run at about 50% of the speed at which it would run > on an uncontended system. > > Having one of the workloads run at 95% of the > uncontended speed and the other workload at 5% > is "not fair" (to put it diplomatically).
As I wrote in the mail to Vivek, I think that providing multiple policies, on a per disk time basis, on a per iosize basis, maximum rate limiting or etc would be good for users.
Thanks, Ryo Tsuruta
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