Re: bio too big device

[Jens Axboe <axboe@suse.de>]

On Wed, Mar 12 2003, Neil Brown wrote:
> On Tuesday March 11, scott-kernel@thomasons.org wrote:
> > I frequently receive this message in my syslog, apparently 
> > whenever there are periods of significant write activity:
> > 
> >     bio too big device ide0(3,7) (256 > 255)
> >     bio too big device ide1(22,6) (256 > 255)
> > 
> > It's worth noting that on this system I have had ongoing trouble 
> > with system stability during write activity as well, using a 
> > wide variety of 2.5.x kernels, even though at the time of this 
> > symptom things are apparently running fine.
> > 
> > Filesystems are all ext3 on top soft raid0 devices. This happens 
> > to be 2.5.64, but it has been happening for at least the last 
> > 5-6 versions.
> > 
> > Ideas? Any further debugging output I can provide?
> 
> 
> raid0 doesn't really work well in 2.5 yet.... as you have noticed.
> 
> We really need to grab the bio splitting code out of md/dm.c and use
> it to split bios that are too big or that cross device boundaries.
> 
> any volunteers??

I can give it a shot

-- 
Jens Axboe