On Sun, 17 Jul 2011, Lutz Vieweg wrote:
What is really an important factor for SSD performance: The controller.
The same SSDs perform with significantly lower latency for us when
connected to SATA controller channels than when connected to SAS
controllers (and they perform abysmal when used as hardware-RAID
constituents, in comparison).
Interesting.
I think it depends a lot on the controller. On a Dell server with PERC5/i
RAID controller (actually made by LSI) I saw some performance degradation
but not enough that I'd consider it a deal-breaker for situations where I
really cared about the RAID functionality, more than about the loss of
performance. After all, the latency is still massively lower than it is
with spinning disk.
I have a really great Areca RAID controller in a different server, but
unfortunately it's in use and it'll be a while before I get another one I
can use for testing. Given how well it does in other respects, I have high
hopes for it.
Best,
--
Tom De Mulder <tdm27@xxxxxxxxx> - Cambridge University Computing Service
+44 1223 3 31843 - New Museums Site, Pembroke Street, Cambridge CB2 3QH
-> 18/07/2011 : The Moon is Waning Gibbous (83% of Full)
--
To unsubscribe from this list: send the line "unsubscribe linux-raid" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
