Re: stripe_cache_size and performance
From: Justin Piszcz <hidden>
Date: 2007-06-26 15:54:24
I repeat: what does the patch do (or is this no longer applicable)? This was for if your stripe_cache_size was above a certain number, it would run at 1-3MB/s rebuild speed. You can always force with the min parameter. Forcing it you should get good speed, faster than 1-3MB/s anyway :) Justin. On Tue, 26 Jun 2007, Jon Nelson wrote:
On Tue, 26 Jun 2007, Justin Piszcz wrote:quoted
On Tue, 26 Jun 2007, Jon Nelson wrote:quoted
On Tue, 26 Jun 2007, Justin Piszcz wrote:quoted
On Tue, 26 Jun 2007, Jon Nelson wrote:quoted
On Mon, 25 Jun 2007, Justin Piszcz wrote:quoted
Neil has a patch for the bad speed.What does the patch do?I repeat: what does the patch do (or is this no longer applicable)?quoted
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sync_speed_max defaults to 200000 on this box already.Altering sync_speed_min...quoted
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I tried a binary search of values between the default (1000) and 60000 which resulted in some pretty weird behavior: at values below 26000 the rate (also confirmed via dstat output) stayed low. 2-3MB/s. At 26000 and up, the value jumped more or less instantly to 70-74MB/s. What makes 26000 special? If I set the value to 20000 why do I still get 2-3MB/s actual?quoted
Sounds quite strange, what chunk size are you using for your RAID?The default: 64 md0 : active raid5 sdc4[2] sda4[0] sdb4[1] 613409664 blocks level 5, 64k chunk, algorithm 2 [3/3] [UUU] -- Jon Nelson [off-list ref] - 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.html