Hi Vitaliy,
Similar to Stefan, we have a bunch of Micron 5200's (3.84TB ECO SATA version) in a Ceph cluster (Nautilus) and performance seems less than optimal. I have followed all instructions on your site (thank you for your wonderful article btw!!), but I haven't seen much change. The only thing I could think of is that "maybe" disabling the write cache only takes place upon a reboot or power cycle? Is that necessary? Or is it a "live" change? I have tested with the cache disabled as well as enabled on all drives. We're using fio running in a QEMU/KVM VM in an OpenStack cluster, so not "raw" access to the Micron 5200's. OSD (Bluestore) nodes run CentOS 7 using a 4.18.x kernel. Testing doesn't show any, or much, difference, enough that the variations could be considered "noise" in the results. Certainly no change that anyone could tell. Thought I'd check to see if you, or anyone else, might have any suggestions specific to the Micron 5200. We have some Micron 5300's inbound, but probably won't have them here for another few weeks due to Micron's manufacturing delays, so will be able to test these raw drives soon. I will report back after, but if you know anything about these, I'm all ears. :) Thank you! Eric From: ceph-users [mailto:ceph-users-boun...@lists.ceph.com] On Behalf Of Stefan Bauer Sent: Tuesday, January 14, 2020 10:28 AM To: undisclosed-recipients Cc: ceph-users@lists.ceph.com Subject: Re: [ceph-users] low io with enterprise SSDs ceph luminous - can we expect more? [klartext] Thank you all, performance is indeed better now. Can now go back to sleep ;) KR Stefan -----Ursprüngliche Nachricht----- Von: Виталий Филиппов <vita...@yourcmc.ru> Gesendet: Dienstag 14 Januar 2020 10:28 An: Wido den Hollander <w...@42on.com>; Stefan Bauer <stefan.ba...@cubewerk.de> CC: ceph-users@lists.ceph.com Betreff: Re: [ceph-users] low io with enterprise SSDs ceph luminous - can we expect more? [klartext] ...disable signatures and rbd cache. I didn't mention it in the email to not repeat myself. But I have it in the article :-) -- With best regards, Vitaliy Filippov
_______________________________________________ ceph-users mailing list ceph-users@lists.ceph.com http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
