On Wed, 14 Mar 2012, Shaohua Li wrote:
Maybe the discard runs slow with small size request in the disk. please drop patch "blk: add plug for blkdev_issue_discard" and try again. Since we can't do merge, the plug just introduces latency.
Tried again without the patch applied, but there is only a very small performance increase (520->600 agains 4000 fps without discard). The benchmark creates lots of small files (2 KiB) and deletes them again.
if it doesn't help, please capture a blktrace when you do the benchmark and send it to me.
Ok, I will do this tomorrow. Need some sleep :-) Thanks for your work on supporting discard in MD! Regards, Holger -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
