Re: 2.6.29.1 vs 2.6.27.21 ext4 performance problem

[Alexander V. Lukyanov]

On Fri, Apr 10, 2009 at 12:36:20PM -0400, Theodore Tso wrote:
> Does the differences go away if you do echo 0 into
> /sys/fs/ext4/<dev>/inode_readahead_blks?

Yes! Thanks for the tip. I think the problem here is that there
are lots of files (2M per file system) and the access is random.

> Are you seeing an increase in time, or decrease in transactions per
> second, or just that there is is an increase in read rates?

Load average goes up from 6 to 30, and request latency increases.

-- 
   Alexander..
--
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/