Sound skipping problems

[Jeff Roberson]

On Wed, 8 Jun 2005, Jean-Yves Lefort wrote:

> On Wed, 8 Jun 2005 09:57:15 -0400 (EDT)
> Jeff Roberson <jroberson at chesapeake.net> wrote:
>
> > On Wed, 8 Jun 2005, Jean-Yves Lefort wrote:
> >
> > > On Wed, 8 Jun 2005 12:48:44 +0200
> > > Simon Barner <barner at FreeBSD.org> wrote:
> > >
> > > > Jeff Roberson wrote:
> > > > > I have a patch that should greatly improve the sound skipping problems
> > > > > people have under heavy io load.  Several people sent me traces that
> > > > > showed the buf daemon running for hundreds of milliseconds with Giant
> > > > > held, which can hold up the pcm code.  The patch is available at:
> > > > >
> > > > > http://www.chesapeake.net/~jroberson/flushbuf.diff
> > > >
> > > > [...]
> > > >
> > > > Can I use the patch on 5.4-STABLE? It applies cleanly (with offset,
> > > > though), but I prefer to ask before doing useless tests.
> > >
> > > I've just tested it on 5.4-RELEASE, and it causes the system to hang
> > > after a few seconds of heavy disk I/O.
> >
> > I have updated the patch to partially revert some earlier behavior.  The
> > hang didn't happen on my machine because I have more memory, but I'm
> > confident of the cause.  I updated it in place, feel free to try it on
> > current or 5.x.
>
> This one works, and completely removes the sound jitter that used to
> appear under heavy disk I/O (eg. untarring a 50 megs tarball).
>
> Congratulations!

Thanks.  I'd like to get some more experience with it under extreme load
conditions, but I do eventually plan to MFC.

>
> PS: if no problems show up, do you intend to MFC this patch?
>
> --
> Jean-Yves Lefort
>
> jylefort at FreeBSD.org
> http://lefort.be.eu.org/
>