Re: [ceph-users] io-schedulers
Using "noop" makes sense only with ssd/nvme drives. "noop" is a simple fifo and using it with HDDs can result in unexpected blocking of useful IO in case when the queue is poisoned with burst of IO requests like background purge, which would become foreground in such case. > On 5.11.2018, at 23:39, Jack wrote: > > We simply use the "noop" scheduler on our nand-based ceph cluster > > > On 11/05/2018 09:33 PM, solarflow99 wrote: >> I'm interested to know about this too. >> >> >> On Mon, Nov 5, 2018 at 10:45 AM Bastiaan Visser wrote: >> >>> >>> There are lots of rumors around about the benefit of changing >>> io-schedulers for OSD disks. >>> Even some benchmarks can be found, but they are all more than a few years >>> old. >>> Since ceph is moving forward with quite a pace, i am wondering what the >>> common practice is to use as io-scheduler on OSD's. >>> >>> And since blk-mq is around these days, are the multi-queue schedules >>> already being used in production clusters? >>> >>> Regards, >>> Bastiaan >>> ___ >>> ceph-users mailing list >>> ceph-users@lists.ceph.com >>> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com >>> >> >> >> >> ___ >> ceph-users mailing list >> ceph-users@lists.ceph.com >> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com >> > > ___ > ceph-users mailing list > ceph-users@lists.ceph.com > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com ___ ceph-users mailing list ceph-users@lists.ceph.com http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
Re: [ceph-users] io-schedulers
It depends on store backend. Bluestore has it's own scheduler which works properly only with CFQ, while filestore configuration is narrowed to setting OSD IO threads' scheduling class and priority just like using 'ionice' utility. > On 5.11.2018, at 21:45, Bastiaan Visser wrote: > > > There are lots of rumors around about the benefit of changing io-schedulers > for OSD disks. > Even some benchmarks can be found, but they are all more than a few years > old. > Since ceph is moving forward with quite a pace, i am wondering what the > common practice is to use as io-scheduler on OSD's. > > And since blk-mq is around these days, are the multi-queue schedules already > being used in production clusters? > > Regards, > Bastiaan > ___ > ceph-users mailing list > ceph-users@lists.ceph.com > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com ___ ceph-users mailing list ceph-users@lists.ceph.com http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
Re: [ceph-users] io-schedulers
We simply use the "noop" scheduler on our nand-based ceph cluster On 11/05/2018 09:33 PM, solarflow99 wrote: > I'm interested to know about this too. > > > On Mon, Nov 5, 2018 at 10:45 AM Bastiaan Visser wrote: > >> >> There are lots of rumors around about the benefit of changing >> io-schedulers for OSD disks. >> Even some benchmarks can be found, but they are all more than a few years >> old. >> Since ceph is moving forward with quite a pace, i am wondering what the >> common practice is to use as io-scheduler on OSD's. >> >> And since blk-mq is around these days, are the multi-queue schedules >> already being used in production clusters? >> >> Regards, >> Bastiaan >> ___ >> ceph-users mailing list >> ceph-users@lists.ceph.com >> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com >> > > > > ___ > ceph-users mailing list > ceph-users@lists.ceph.com > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com > ___ ceph-users mailing list ceph-users@lists.ceph.com http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
Re: [ceph-users] io-schedulers
I'm interested to know about this too. On Mon, Nov 5, 2018 at 10:45 AM Bastiaan Visser wrote: > > There are lots of rumors around about the benefit of changing > io-schedulers for OSD disks. > Even some benchmarks can be found, but they are all more than a few years > old. > Since ceph is moving forward with quite a pace, i am wondering what the > common practice is to use as io-scheduler on OSD's. > > And since blk-mq is around these days, are the multi-queue schedules > already being used in production clusters? > > Regards, > Bastiaan > ___ > ceph-users mailing list > ceph-users@lists.ceph.com > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com > ___ ceph-users mailing list ceph-users@lists.ceph.com http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
[ceph-users] io-schedulers
There are lots of rumors around about the benefit of changing io-schedulers for OSD disks. Even some benchmarks can be found, but they are all more than a few years old. Since ceph is moving forward with quite a pace, i am wondering what the common practice is to use as io-scheduler on OSD's. And since blk-mq is around these days, are the multi-queue schedules already being used in production clusters? Regards, Bastiaan ___ ceph-users mailing list ceph-users@lists.ceph.com http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
