Re: Linux 2.6.29

Andrew Morton
2009-04-01T21:40:09Z

On Wed, 1 Apr 2009 17:03:38 -0400
lsorense@csclub.uwaterloo.ca (Lennart Sorensen) wrote:

> On Thu, Mar 26, 2009 at 06:25:19PM -0700, Andrew Morton wrote:
> > The JBD journal is a massive designed-in contention point. It's why
> > for several years I've been telling anyone who will listen that we need
> > a new fs. Hopefully our response to all these problems will soon be
> > "did you try btrfs?".
>
> Oh I look forward to the day when it will be safe to convert my mythtv
> box from ext3 to btrfs. Current kernels just have too much IO latency
> with ext3 it seems. Older kernels were more responsive, but probably
> had other places they were less efficient.

Back in 2002ish I did a *lot* of work on IO latency, reads-vs-writes,
etc, etc (but not fsync - for practical purposes it's unfixable on
ext3-ordered)

Performance was pretty good. From some of the descriptions I'm seeing
get tossed around lately, I suspect that it has regressed.

It would be useful/interesting if people were to rerun some of these
tests with `echo anticipatory > /sys/block/sda/queue/scheduler'.

Or with linux-2.5.60 :(