> iops : min= 2, max= 40, avg=21.13, stdev= 6.10, samples=929 > iops : min= 2, max= 42, avg=21.52, stdev= 6.56, samples=926 That looks horrible. We also have a few SATA HDDs in Dell servers and they do about 100-150 IOP/s read or write. Originally, I was also a bit afraid that these disks would drag performance down, but they are on par with the NL-SAS drives. For ceph we use the cheapest Dell disk controller one can get (Dell HBA330 Mini (Embedded)) and it works perfectly. All ceph-disks are configured non-raid, which is equivalent to JBOD mode or pass-through. These controllers have no cache options, if your do, disable all of them. Mode should be write-through. For your disk type I saw "volatile write cache available = yes" on "the internet". This looks a bit odd, but maybe these HDDs do have some volatile cache. Try to disable it with smartctl and do the benchmark again. Best regards, ================= Frank Schilder AIT Risø Campus Bygning 109, rum S14 _______________________________________________ ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an email to ceph-users-leave@xxxxxxx
 |