Re: i/o stalls on 2.4.14-pre3 with ext3

[Linus Torvalds]

On Mon, 29 Oct 2001, Andrew Morton wrote:
>
> Hum.   I did a quick test here.  cvs checkout of a kernel
> tree with source and dest both on the same platter.  Using
> ext2:
>
> 2.4.13: 	1:34
> 2.4.14-pre3:	1:28
> 2.4.14-pre5:	1:37
>
> We need more silly bugs.

Well, considering that the silly bug could result in request queue
corruption, I really suspect you'll be happier without it ;)

The io_request_lock wasn't held in a critical place, which would
potentially improve performance, but ...

> I'll poke at it a bit more.  One perennial problem which
> we face is that there isn't, IMO, a good set of tests for tracking
> changes in thoughput.  All the tools which are readily available
> are good for stress testing and silly corner cases but they
> don't seem to model real-world workloads well.

Agreed.

		Linus