RAID 5 seems slow

nh_nh

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Oct 30, 2011
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Hello,
I set-up 3 Seagate ST1000NM0011 drives in RAID 5 in my new desktop with an SSD for OS and Apps.
I noticed that the RAID is running super slow when I tried viewing pictures (long loading time, and errors in slide show). Any suggestions or tips to improve the read/write speeds?

I am using the on board RAID controller on my P8Z68-V LE Asus MB. All 3 drives are connected to the 3GB/s SATA ports (SSD is on the 6GB/s port). Stripe size is 32KB. Write-back cache is disabled (default).
 

Wamphryi

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There is a certain amount of controversy regarding RAID 5. RAID 5 generally requires a decent RAID Controller to get the best out of it and it often comes with performance liabilities especially on random writes. I would not recommend RAID 5 for most users especially if you are using SATA instead of SAS.
 

pnorman

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May 20, 2010
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My guess would be a drive having problems. Although software RAID5 suffers from the write hole problem, it shouldn't be bad enough to impact it like you describe.

Run a check on the drives. You want to check their SMART status and run any checks your controller allows you to do. I'm not familiar with the intel fakeraid controllers so I'm not sure what you can and can't do.