> Op 27 juni 2017 om 13:26 schreef Mark Nelson <mnelson@xxxxxxxxxx>: > > > > > On 06/27/2017 06:24 AM, Wido den Hollander wrote: > > > >> Op 27 juni 2017 om 13:05 schreef Christian Balzer <chibi@xxxxxxx>: > >> > >> > >> 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. > > FYI: > > https://github.com/ceph/ceph/pull/14727 Aha! Great to see that there. I'll keep an eye out on that PR. Wido > > > > > Wido > > > >> Christian > >> -- > >> Christian Balzer Network/Systems Engineer > >> chibi@xxxxxxx Rakuten Communications > > _______________________________________________ > > ceph-users mailing list > > ceph-users@xxxxxxxxxxxxxx > > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com > > > _______________________________________________ > ceph-users mailing list > ceph-users@xxxxxxxxxxxxxx > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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