Re: stripe_cache_size and performance [BUG with =64kb]
From: Justin Piszcz <hidden>
Date: 2007-06-25 19:49:01
On Mon, 25 Jun 2007, Justin Piszcz wrote:
On Mon, 25 Jun 2007, Justin Piszcz wrote:quoted
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 - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.htmlRunning 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.
Ack, help?? [ 64.032895] Starting XFS recovery on filesystem: md3 (logdev: internal) [ 66.210602] XFS: xlog_recover_process_data: bad clientid [ 66.210656] XFS: log mount/recovery failed: error 5 [ 66.210709] XFS: log mount failed After I ran 64kb it killed my RAID!