2016-09-26 23:08 GMT+02:00 Lindsay Mathieson <lindsay.mathieson@xxxxxxxxx>: > I wouldn't be doing that - very high risk of gluster corruption in the event > of power loss or server crash. Up to 5 seconds of writes could be lost that > way. > > If writes aren't fast enough I'd add a SSD partition for slog. Preferably a > data center quality one. You are right, I don't want to loose some data by using 'sync=disabled' Also, I would like to try to force the use of SLOG to an Enterprise SSD (also used for L2ARC) by setting 'sync=always' In this way all writes are synchronous and made against the SSD. This should also "hide" the overhead of RAIZ2 or RAIDZ3 as writes are on SLOG and not directly on the vpool So: 2x Enterprise SSD (Intel 3600) 1 partition on both is mirrored and used as SLOG The other 2 partitions (one on each SSD) are used as L2ARC and not mirrored (is not possible and has nonsense) Everything configure with 'sync=always' RAIDZ-3 made with 12x 4TB disks (I don't know the resilvering time for a huge vpool like this) In this way, an SSD failure doesn't cause data loss (SLOG is mirrored) and L2ARC cache is automatically disabled by ZFS At the same time, there isn't any write penalty for the RAIZ3 because all writes are made to the SLOG and only after that wrote on the pool What do you think? _______________________________________________ Gluster-users mailing list Gluster-users@xxxxxxxxxxx http://www.gluster.org/mailman/listinfo/gluster-users
