--On 25 May 2010 15:28 +0300 Pasi Kärkkäinen <pa...@iki.fi> wrote:
I've tried contacting Intel to find out if it's true their "enterprise"
SSD has no cache protection on it, and what the effect of turning the
write cache off would have on both performance and write endurance, but
not heard anything back yet.
I guess the problem is not the cache by itself, but the fact that they
ignore the CACHE FLUSH command.. and thus the non-battery-backed cache
becomes a problem.
The X25-E's do apparently honour the 'Disable Write Cache' command -
without write cache, there is no cache to flush - all data is written to
flash immediately - presumably before it's ACK'd to the host.
I've seen a number of other sites do some testing with this - and found
that it 'works' (i.e. with write-cache enabled, you get nasty data loss if
the power is lost - with it disabled, it closes that window). But you
obviously take quite a sizeable performance hit.
We've got an X25-E here which we intend to test for ourselves (wisely ;) -
to make sure that is the case...
-Karl
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