Responses inline. I have a last question. Why is the bench performed using writes of 4 KiB. > Is any reason to choose that over another another value? > > Yes, the mClock scheduler considers this as a baseline in order to estimate costs for operations involving other block sizes. This is again an internal implementation detail.
On my lab, I tested with various values, and I have mainly two type of > disks. Some Seagates and Toshiba. > > If I do bench with 4KiB, what I get from Seagate is a result around 2000 > IOPS. While the Toshiba is more arround 600. > > If I do bench with 128KiB, I still have results arround 2000 IOPS for > Seagate, but Toshiba also bench arround 2000 IOPS. And from the rados > experiment I did, having osd_mclock_max_capacity_iops_hdd set to 2000 on > that lab setup is the value I get the most performance from my rados > experiments, both with Segate and Toshiba disks. > > I would currently suggest setting osd_mclock_max_capacity_iops_hdd to values you measured with fio as that is more realistic. Like I mentioned, there are some improvements coming around this area that would allow users to have greater control on setting a realistic benchmark value. -Sridhar _______________________________________________ ceph-users mailing list -- ceph-users@ceph.io To unsubscribe send an email to ceph-users-le...@ceph.io
