Re: [patch] rearrange kioctx and aio_ring_info

From: Dave Jones
Date: Thu Oct 12 2006 - 20:04:42 EST


On Thu, Oct 12, 2006 at 04:25:54PM -0700, Chen, Kenneth W wrote:
> The following patch is result of our kernel data latency analysis on a
> large database setup (128 logical CPU, 1 TB memory, a couple thousand
> disks). The analysis is done at an individual cache line level through
> hardware performance monitor unit. What we did essentially is to collect
> data access latency on every kernel memory address and look for top 50
> longest average access latency. The hardware performance unit also keeps
> track of instruction address for each collected data access. This allows
> us to further associate each of the top 50 cache lines to instruction
> sequences that caused long latency.

Do you have performance numbers of before/after this change ?
How much is it worth?

Dave

--
http://www.codemonkey.org.uk
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/