When RAID 10 is SLOWER than RAID 1, why?

Posted by Paul on Server Fault See other posts from Server Fault or by Paul
Published on 2011-02-19T02:15:47Z Indexed on 2011/02/19 7:26 UTC
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Filed under:

raid

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dell

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oracle11g

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perc

We have a Dell 2950 with PERC and 14 external SAS 15K 73GB drives. An Oracle database job takes 3 hours to run with the drives set as hardware RAID 10 (striped across 7 mirrored pairs). The same job with the drives in RAID 1 takes only 1 hour. OS is Win 2008 R2 I think.

Before we change the RAID level (with considerable downtime) on the production box, does anyone know why we're seeing this odd result, and if there's a better way to fix it?

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