On Mon, 25 Jun 2007, Justin Piszcz wrote:

On Mon, 25 Jun 2007, Bill Davidsen wrote:

quoted

Justin Piszcz wrote:

quoted

I have found a 16MB stripe_cache_size results in optimal performance after 
testing many many values :)

We have discussed this before, my experience has been that after 8 x stripe 
size the performance gains hit diminishing returns, particularly for 
typical write instead of big aligned blocks, possibly with O_DIRECT. I 
would suggest that as a target even on a low memory machine.

Do your tests show similar? I was only able to test three and four drive 
setups using dedicated drives.

-- 
bill davidsen [off-list ref]
CTO TMR Associates, Inc
Doing interesting things with small computers since 1979

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Running test with 10 RAPTOR 150 hard drives, expect it to take awhile until I 
get the results, avg them etc. :)

128k,256k,512k,1024k,2048k,4096k,8192k,16384k

Justin.

Definitely a kernel bug, I set it to 64kb and it stayed in D-state until I 
ran alt-sysrq-b.

Pretty nasty!

Justin.