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sunnyj

macrumors 6502
Original poster
Oct 18, 2010
430
9
Vancouver, British Columbia
i have two 2tb WD caviar black drives raided together. on a newly created raid the aja speed test gives me about 250 read and write speed. now its been about a month since i created the raid and the speed has degraded to about 140 read and write. even when the raid is empty the speed is 140. what could be causing the decrease in speed? i tried to verify and repair disc permissions with no speed gain.
 
Hello,

I'm getting 270 r/w on the exact same set-up with same drives, and the RAID has been up for quite a few months now... Not sure what's wrong with yours.

If you can empty the RAID0, why not try to rebuild it?

Loa
 
i have 2 sets of this raid 0 setup and on both sets the performance is reduced.

the raid set that i emptied i rebuilt it and the r/w is about 260. its a big inconvenience if i have to recreate the raids every month or so.

what block size are you using & are you editing videos?
 
Hello,

32K and no. I do move large files, but nowhere near as frequently as someone editing video.

Loa
 
Hello,

32K and no. I do move large files, but nowhere near as frequently as someone editing video.

Loa
i move huge files and the drives are always R/W'ing when I'm encoding videos.

Does a re-format fix it? I'm just thinking that maybe it is fragmented?
like loa said, it can't be fragmented because if the raid is empty the speed should return to normal.



empty 1 month old raid
ScreenShot2012-02-20at15603PM.png

newly created raid
ScreenShot2012-02-20at21214PM.png
 
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