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Article Feedback - Swapping boot drives around
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 Tests not accurate
Author: Luke 
Date:   15-01-06 22:36

I noticed that with one test you used identical drives, but with other tests you used different models and even brands of drives. i've read information on hackers@ and other sources in the past stating that when setting up a raid environment, you should try to use the same type of drives. Using drives with different performance characteristics can cause one drive to be "faster" most of the time and defeat the purpose. If you think about it, raid 1 must write data to both disks and can read from either one. Each vendor has different cache and write timings, etc.

That being said, I have a raid 1 setup using gmirror. At the time i setup the box, it was running 5.4 with a patched ata driver to support my sata controller. The onboard raid was not supported. I upgraded the machine to 6.0 release and noticed a large improvement in gmirror. The drives are identical SATA western digital 80gb drives with 8mb cache. (same model, etc) Performance since I upgraded to 6.0 release has been excellent. The array often beats my single ultra 160 seagate 6mb cache 72gb 10k drive.

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 Yes, they are accurate. :)
Author: Dan 
Date:   13-02-06 16:51

I use two disks from different manufacturers to improve the reliability of the RAID array. If there is a defect in the drive, and both drives are different brands, you're much less likely to have a double failure in a short period of time (i.e. you lose both drives).


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