Hi Mark/Alexandre, The results are with journal and data configured in the same SSD ? Also, how are you configuring your journal device, is it a block device ? If journal and data are not in the same device result may change. BTW, there are SSDs like SanDisk optimas drives that is using capacitor backed DRAM and thus always ignore these CMD_FLUSH command since drive guarantees that once data reaches drive, it will power fail safe.So, you don't need kernel patch. Optimus random write performance is ~15K (4K io_size). Presently, I don't have any write performance data (on ceph) with that, I will run some test with that soon and share. Thanks & Regards Somnath -----Original Message----- From: ceph-users [mailto:ceph-users-bounces@xxxxxxxxxxxxxx] On Behalf Of Mark Kirkwood Sent: Tuesday, September 16, 2014 3:36 PM To: Alexandre DERUMIER; Sebastien Han Cc: ceph-users at lists.ceph.com Subject: Re: [Single OSD performance on SSD] Can't go over 3, 2K IOPS On 17/09/14 08:39, Alexandre DERUMIER wrote: > Hi, > >>> I?m just surprised that you?re only getting 5299 with 0.85 since >>> I?ve been able to get 6,4K, well I was using the 200GB model > > Your model is > DC S3700 > > mine is DC s3500 > > with lower writes, so that could explain the difference. > Interesting - I was getting 8K IOPS with 0.85 on a 128G M550 - this suggests that the bottleneck is not only sync write performance (as your S3500 do much better there), but write performance generally (where the M550 is faster). Cheers Mark _______________________________________________ ceph-users mailing list ceph-users at lists.ceph.com http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com ________________________________ PLEASE NOTE: The information contained in this electronic mail message is intended only for the use of the designated recipient(s) named above. If the reader of this message is not the intended recipient, you are hereby notified that you have received this message in error and that any review, dissemination, distribution, or copying of this message is strictly prohibited. If you have received this communication in error, please notify the sender by telephone or e-mail (as shown above) immediately and destroy any and all copies of this message in your possession (whether hard copies or electronically stored copies).
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