Am 24.12.2014 um 02:02 schrieb Andrew Savchenko: >> Ad "slow": what kind of hardware did you use and how many nodes/osds? > > We used 3 servers, where each server was both node and osd (that's > our hardware limitation). Each machine had hardware alike 2x > Xeon E5450, 16 GB and 2 Gbps network connectivity (via bonding of > two 1 Gbps interfaces). > > We went through a lot of software and kernel tuning, this helped to > solve many issues, but not all of them: ceph nodes still got kernel > panics once in a while. This was unacceptable and we moved for > other approaches to our issues.
Hmm, that dampens my enthusiasm ;-) I watched a presentation on youtube yesterday where they recommended one SSD as journal per ~4 harddisks ... and 4-8 hard disks per OSD node maximum (if I remember correctly). Plus ~1 GHz / 1 core of CPU per OSD ... as a rule of thumb. And 500 MB RAM per OSD ... that were the recommendations in http://youtu.be/C3lxGuAWEWU - Did you have the journal separated on SSDs? I think that would make quite a difference both in performance and cost ;) Do you remember the kernel version and ceph version? How many disks / OSDs? Sorry for being so curious .. Thanks, Stefan
