Extreme console latency during disk IO (8.0-RC1, previous releases also affected according to others)

[Luigi Rizzo]

On Tue, Oct 13, 2009 at 09:58:09AM +0200, Thomas Backman wrote:
> 
> On Oct 13, 2009, at 12:35 AM, Luigi Rizzo wrote:
...
> >hi,
> >this issue (not specific to FreeBSD, and not new -- it has been
> >like this forever) is discussed in some detail here
> >
> >	http://www.bsdcan.org/2009/schedule/events/122.en.html
> >
> >The following code (a bit outdated) can help
> >
> >http://lists.freebsd.org/pipermail/freebsd-stable/2009-March/048704.html
> >
> >cheers
> >luigi
> Hmm, how stable would you say the code is? (And/or has there been any  
> progress since March?)
> I'd prefer something that I feel confident in using in production, and  
> the warning in the README clearly says "stay away!".

Maybe not for production but if you want to use it on a test box
to see if it helps then it is definitely reliable (as long as you
don't exercise too much the plugging and unplugging schedulers on
a mounted filesystems).

I have been using the code for perhaps a couple of months on my
desktop machine and no data loss, the only reason it is not loaded
now is that it is not loaded by default at boot time.

cheers
luigi