Brief freezes with -current as of early last week

[Jeremy Chadwick]

PREEMPTION isn't a kernel option -- it's something you tweak in
/usr/include/machine/param.h (or /usr/src/include/...), unless this
procedure has changed recently...

-- 
| Jeremy Chadwick                                 jdc at parodius.com |
| Parodius Networking                        http://www.parodius.com/ |
| UNIX Systems Administrator                   Mountain View, CA, USA |
| Making life hard for others since 1977.                             |

On Mon, Sep 20, 2004 at 05:16:30PM +0100, Nik Clayton wrote:
> On Mon, Sep 20, 2004 at 12:00:19PM -0400, David Schultz wrote:
> > This sounds like an I/O hang.  I've been having similar problems
> > related to WRITE_DMA and READ_DMA timeouts from the ata driver in
> > the last week or so, as discussed last week on this list.  Are you
> > seeing these messages from the kernel?  
> 
> Like these?
> 
> ad0: TIMEOUT - READ_DMA retrying (2 retries left) LBA=47240127
> ad0: WARNING - READ_DMA no interrupt but good status
> ad1: TIMEOUT - READ_DMA retrying (2 retries left) LBA=165370263
> ad1: WARNING - READ_DMA no interrupt but good status
> 
> ad0 is a 2 year old 40GB disk, ad1 is 1 week old 120GB disk.
> 
> > Julian suggested disabling
> > preemption, which I haven't tried yet, but other people report
> > limited success.
> 
> I'm not running a kernel with 'options PREEMPTION' compiled in...
> 
> N
> -- 
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