Hi Udo, thanks for reply, I thought already that my message was missed the list. Not sure if understand correctly. Do you mean "rbd cache = true"? If yes, then this is RBD client cache behavior, not on OSD side, isn't it?"
Regards Ahmed On Sun, Jan 22, 2017 at 6:45 PM, Udo Lembke <ulem...@polarzone.de> wrote: > Hi, > > I don't use mds, but I thinks it's the same like with rdb - the readed > data are cached on the OSD-nodes. > > The 4MB-chunks of the 3G-file fit completly in the cache, the other not. > > > Udo > > > On 18.01.2017 07:50, Ahmed Khuraidah wrote: > > Hello community, > > > > I need your help to understand a little bit more about current MDS > > architecture. > > I have created one node CephFS deployment and tried to test it by fio. > > I have used two file sizes of 3G and 320G. My question is why I have > > around 1k+ IOps when perform random reading from 3G file into > > comparison to expected ~100 IOps from 320G. Could somebody clarify > > where is read buffer/caching performs here and how to control it? > > > > A little bit about setup - Ubuntu 14.04 server that consists Jewel > > based: one MON, one MDS (default parameters, except mds_log = false) > > and OSD using SATA drive (XFS) for placing data and SSD drive for > > journaling. No RAID controller and no pool tiering used > > > > Thanks > > > > > > > > _______________________________________________ > > 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
