Status of fstrim & MD-RAID

[Roberto Ragusa]

On 09/17/2013 04:34 PM, Jorge Fábregas wrote:

> Thanks Heinz.  Now I created a RAID 1 device (with just one device;
> didn't know one could do that) and used fstrim and indeed it's working.

Everyone knows about RAID-1 with two devices, not many know about three or more devices,
almost nobody knows about the one device trick ("I only have one disk, but I'm planning
to turn this stuff into RAID-1 next month").

;-)

Just an additional consideration:
If the RAID-1 resyncs for any reason, a copy will be done from one SSD to the other,
so the second SSD will be apparently 100% used, from the "discard" point of view.
Running fstrim will be needed to recreate the holes.

-- 
   Roberto Ragusa    mail at robertoragusa.it