On 2010-05-19 08.32, sensille wrote:
Don wrote:
With that in mind- Is anyone using the new OCZ Vertex 2 SSD's as a ZIL?
They're claiming 50k IOPS (4k Write- Aligned), 2 million hour MTBF, TRIM
support, etc. That's more write IOPS than the ZEUS (40k IOPS, $$$$$) but at
half the price of an Intel X25-E (3.3k IOPS, $400).
Needless to say I'd love to know if anyone has evaluated these drives to see if
they make sense as a ZIL- for example- do they honor cache flush requests? Are
those sustained IOPS numbers?
In my understanding nearly the only relevant number is the number
of cache flushes a drive can handle per second, as this determines
my single thread performance.
Has anyone an idea what numbers I can expect from an Intel X25-E or
an OCZ Vertex 2?
I don't know about OCZ Vertex 2, but the Intel X25-E
roughly halves it's IOPS number when you disable it's
write cache (IIRC, it was in the range 1300-1600
writes/s or so).
Since it ignores Cache Flush command and it doesn't
have any persistant buffer storage, disabling the write
cache is the best you can do.
Note that there were reports of the Intel X25-E loosing
a write even though you had the write cache disabled!
Since they still haven't fixed this, after more than a
year on the market, I believe it rather qualifies into
the "hardly usable toy" class. I am very disappointed,
I had hopes for a new class of cheap but usable flash
drives. Maybe some day...
/ragge
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