9 aug 2008 kl. 00.47 skrev Greg Smith:

On Fri, 8 Aug 2008, Henrik wrote:

It feels like there is something fishy going on. Maybe the RAID 10 implementation on the PERC/6e is crap?

Normally, when a SATA implementation is running significantly faster than a SAS one, it's because there's some write cache in the SATA disks turned on (which they usually are unless you go out of your way to disable them). Since all non-battery backed caches need to get turned off for reliable database use, you might want to double- check that on the controller that's driving the SATA disks.

Lucky for my I have BBU on all my controllers cards and I'm also not using the SATA drives for database. That is why I bought the SAS drives :) Just got confused when the SATA RAID 5 was sooo much faster than the SAS RAID10, even random writes. But I should have realized that SAS is only faster if the number of drives are equal :)

Thanks for the input!

Cheers,
Henke



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* Greg Smith [EMAIL PROTECTED] http://www.gregsmith.com Baltimore, MD

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