> Op 27 juni 2017 om 13:05 schreef Christian Balzer <[email protected]>: > > > On Tue, 27 Jun 2017 11:24:54 +0200 (CEST) Wido den Hollander wrote: > > > Hi, > > > > I've been looking in the docs and the source code of BlueStore to figure > > out if it issues TRIM/Discard [0] on SSDs and I haven't been able to find > > an answer. > > > > Does BlueStore/BlueFS issue these commands to give back the space to the > > underlying device? > > > > For SSDs it improves both write performance and their lifespan, so it would > > be a very nice to have feature. > > > > SATA 3.1 has "Queued TRIM Command" which allows it to be 'async' in the > > controller. > > > If it were that last bit, I'd be for it, if it isn't then something that > you can fully control akin to fstrim would be a much better idea. >
Problem is that you can't run fstrim on BlueStore since it's not a mounted filesystem like XFS. Therefor TRIM/Discard would have to be issued by the OSD. > That being said, I'm disinclined to deploy any SSDs that actually REQUIRE > trim/discard to maintain their functional levels. > I wouldn't say require, but it never hurts to actually do a TRIM/Discard when it comes to the lifespan of a SSD. However, I'm curious if this is actually in BlueStore or not. Wido > Christian > -- > Christian Balzer Network/Systems Engineer > [email protected] Rakuten Communications _______________________________________________ ceph-users mailing list [email protected] http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
