On Feb 7, 2014, at 2:00 AM, sam tygier <samtyg...@yahoo.co.uk> wrote:
> On 06/02/14 23:35, Chris Murphy wrote: >> On Feb 6, 2014, at 7:43 AM, Wade Hampton <wadehampto...@gmail.com> wrote: >>> - mount using discard (or use the fstrim program periodically) >> >> The discard/TRIM debate can be found in the archives and also on devel@ >> archives, and on XFS archives. Not all SSDs perform that well with discard >> mount option because TRIM is a non-queued command, therefore for TRIM >> commands to be issued the drive cache must be cleared of all other commands >> and this can actually make things slower. So really it depends on your >> workload type, and the SSD you're using. I wouldn't assume you must have >> this enabled. Pretty much every source on this has been wrong, notable the >> crap resulting from coverage of Ubuntu moving to discard by default. >> > > Ubuntu will be using a cronjob that calls fstrim, not the discard mount > option. They found that the discard option cause a small performance hit. Oops, that's right, thanks for the correction. I think they've gone with the better generic option using fstrim instead of discard: better in that it'll eventually get the SSD information on what blocks are no longer used by the file system, but also won't hang up certain SSDs that perform non-queued TRIM function slowly. Chris Murphy -- users mailing list users@lists.fedoraproject.org To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Fedora Code of Conduct: http://fedoraproject.org/code-of-conduct Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines Have a question? Ask away: http://ask.fedoraproject.org
