On Mon, Aug 09, 2010 at 05:07:23PM -0400, Christoph Hellwig wrote:

Can you try with the new barrier implementation in the

	[PATCH, RFC] relaxed barriers

by making cache flushes just that and not complicated drain barrier
it should speed this case up a lot.

Indeed it does!  The barrier count increases to about 21000, but I also see
much higher throughput, about 830 transactions per second (versus 12000 and 760
respectively before Tejun's patch).

--D