On Wed, 3 Feb 2016 22:42:32 -0700 Robert LeBlanc wrote: > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA256 > > > On Wed, Feb 3, 2016 at 9:00 PM, Christian Balzer wrote: > > On Wed, 3 Feb 2016 16:57:09 -0700 Robert LeBlanc wrote: > > > That's an interesting strategy, I suppose you haven't run into the > > issue I wrote about 2 days ago when switching to forward while running > > rdb bench? > > We haven't, but we are running 0.94.5. If you are running Firefly, > that could be why. > I just finished downgrading my test cluster from testing to Jessie and then upgrading Ceph from Firefly to Hammer (that was fun few hours). And I can confirm that I don't see that issue with Hammer, wonder if it's worth prodding the devs about. I sorta dread the time the PG upgrade process will take when going to Hammer on the overloaded production server. But then again, a fix for Firefly is both unlikely and going to take too long for my case anyway. > > In my case I venture that the number of really hot objects is small > > enough to not overwhelm things and that 5K IOPS would be all that > > cluster ever needs to provide. > > We have 48x Micron M600 1TB drives. They do not perform as well as the > Intel S3610 800GB which seems to have the right balance of performance > and durability for our needs. Since we had to under provision the > M600s, we should be able to get by with the 800GB just fine. Once we > get the drives swapped out, we may do better than the 10K IOPs as well > as the recency fix going into the next version of Hammer it will help > with writeback. With our new cluster, we did fine in writeback mode > until we hit that 10K IOP limit, then we started getting slow I/O > messages, turning it to forward mode and things sped up a lot. > Yeah, I'm using 800GB DC S3610s as well. Christian > > - ---------------- > Robert LeBlanc > PGP Fingerprint 79A2 9CA4 6CC4 45DD A904 C70E E654 3BB2 FA62 B9F1 > -----BEGIN PGP SIGNATURE----- > Version: Mailvelope v1.3.4 > Comment: https://www.mailvelope.com > > wsFcBAEBCAAQBQJWsuTFCRDmVDuy+mK58QAAxO0P/R2mkmoOE/YSD9Ea8uUz > XBlOI2eibT5DGK6jR/hVL0V0dInNtVM+4yGWEmvJm5nxnwbx+EQd+lCTFQ5y > WouwGQLCMOCiy0rgduTeTwyGHjeIbloGoYYhZQPEFHOMt1lcKcwiEbrEKUYN > csUmEApK2aiPna5dMsvQs39/oATuid9Aec8VwcyCozzWUe/UziXVFhdWw3Q5 > 2mz8AuOhrmFqd7iyFN9Dici/DXLhBxWgg4PWn81Ggzq/5LHGyyV6A0jiLCBH > /B9rUCOmdfBvdK/GxCG7iUqIjVvIR2mtYFkCu7VL/exsnxuGRB2RHYcXgfVH > rMbZ+gbK/T4XZvUTwDpsfzkEwOTlCuhkcMcHyZLl/MdmcNVXP2+cB9TaCbPI > Hn2H0CuXqQhZ73znQSVS66/QA7s4W5LzMiAUZnOdIX05eVLnZEgstFr8fSEn > O95Y4jLYyQB+CIF9IfA6fgGsvnrs0rTGvYEThk6HL1sa6uVwR5PESVJpapS5 > smUenHyp7OPTVdVpGzJh6VOOB08lcA7JFkicCSG1iXTPucuGkuVNMQ2i0LNb > DA/WAbwUqSK1XHIIu2NCaDZsIbSPwWGXj2uwfNFgSzss1UqAVEF0cBfY6c6n > 3bdPwY2SgOc7nB+LGDQM6dsaFqDS1E490cFwc85uDTkVOBL0JcAJHAvZV2lD > w4Tj > =H+mV > -----END PGP SIGNATURE----- > -- Christian Balzer Network/Systems Engineer chibi@xxxxxxx Global OnLine Japan/Rakuten Communications http://www.gol.com/ _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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