Re: Contemplating SSD Hardware RAID

Am Dienstag, 21. Juni 2011 05:54:26 schrieb Dan Harris:
> I'm looking for advice from the I/O gurus who have been in the SSD game
> for a while now.
>
> I understand that the majority of consumer grade SSD drives lack the
> required capacitor to complete a write on a sudden power loss. But,
> what about pairing up with a hardware controller with BBU write cache?
> Can the write cache be disabled at the drive and result in a safe setup?
>
> I'm exploring the combination of an Areca 1880ix-12 controller with 6x
> OCZ Vertex 3 V3LT-25SAT3 2.5" 240GB SATA III drives in RAID-10. Has
> anyone tried this combination? What nasty surprise am I overlooking here?
>
> Thanks
> -Dan

Wont work.

period.

long story: the loss of the write in the ssd cache is substantial.

You will loss perhaps the whole system.

I have tested since 2006 ssd - adtron 2GB for 1200 Euro at first ...

i can only advice to use a enterprise ready ssd.

candidates: intel new series , sandforce pro discs.

i tried to submit a call at apc to construct a device thats similar to a
buffered drive frame (a capacitor holds up the 5 V since cache is written
back) , but they have not answered. so no luck in using mainstream ssd for
the job.

loss of the cache - or for mainstream sandforce the connection - will result
in loss of changed frames (i.e 16 Mbytes of data per frame) in ssd.

if this is the root of your filesystem - forget the disk.

btw.: since 2 years i have tested 16 discs for speed only. i sell the disc
after the test. i got 6 returns for failure within those 2 years - its really
happening to the mainstream discs.

--
Mit freundlichen Grüssen
Anton Rommerskirchen