On Sun, 25 Jun 2000, Robert Swindells wrote:

> >> I've noticed this before, but today I've sat down and tested. When two
> >> drives are in heavy use on a CATS it completely locks. For instance if
> >> either of the two following commands are run separately, everything works
> >> fine. If both are run at the same time the machine will completely lock.
> 
> >This affects diskful Sharks too, although much less so with -current
> >compared to the 1.4 branch. It has also been reported on some i386
> >installations.
> 
> My CATS will lock up under heavy use with just one drive.
> 
> I can reproduce it every time if I try to build the Jikes Java compiler.

I seem to recall a similar discussion with ARMLinux on the CATS, so maybe
there is a hardware element to the problem as well as an OS-related
problem. Perhaps someone who remembers better than I could elaborate? I've
also seen the problem on a RiscPC under heavy swapping which I put down to
UVM funnies (as I would have with the Jikes example above). However, the
tests that I did were simple extended reads from the raw device. The
problem certainly seems to be internal IDE related. Has the problem been
seen with SCSI on a CATS or with a Promise IDE card?

--
Dr. Stephen Borrill