Messages in this thread | | | Date | Wed, 23 Apr 2014 14:58:35 -0400 | From | Vivek Goyal <> | Subject | Re: [PATCH RFC] blkcg: prepare blkcg knobs for default hierarchy |
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On Wed, Apr 23, 2014 at 02:52:31PM -0400, Tejun Heo wrote: > Hello, > > On Wed, Apr 23, 2014 at 01:17:20PM -0400, Vivek Goyal wrote: > > I think we should just require two. One for measuring rate in terms > > of IOPS and other for measuring rate in terms of [kMG]B/sec. > > I meant between cfq and blk-throttle. Why do we have separate stats > for them to present ultimately the same numbers?
Oh, sorry, I had misunderstood your question.
- Number of IOs serviced will be different at throttling layer and CFQ layer as throttling accounts IO in terms of bios and CFQ accounts in terms of number of requests.
- CFQ might not be operational on a device while throttling might be on and one needs bytes stats.
- In a custom kernel throttling might not be on and CFQ is on and one needs the stats.
So I think we do require duplication of some stats across throttling and CFQ, isn't it?
Thanks Vivek
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