scavenge_mutable_list: strange object?

Andrew Cheadle amc4@doc.ic.ac.uk
Wed, 9 Jul 2003 11:54:01 +0100 (BST)


Johannes,

I think Simon M who could help you with this is away, so I'll try and
help you in the short term.

This is most likely a bug in the generational garbage collector.
I'm guessing you can't reproduce the problem very easily? If it happens
say 7 in 10 times, I can have a look at it for you if you send the code
over with instructions to cause failure.

One thing you can try to prevent this is to use the semi-space collector
instead of the generational:

<snip from manual>
Specifying 1 generation with +RTS -G1  gives you a simple 2-space
collector, as you would expect. In a 2-space collector, the -A option
(see above) specifies the minimum allocation area size, since the
allocation area will grow with the amount of live data in the heap. In a
multi-generational collector the allocation area is a fixed size (unless
you use the -H option, see below).
</end snip>

Hope that helps.

Cheers

Andy

On Wed, 9 Jul 2003, Johannes Waldmann wrote:

>I sometimes get this error:
>
>>  internal error: scavenge_mutable_list: strange object? 3
>
>( large program, running on debian linux on i368, compiled with
>ghc-6.0 -pgmc gcc-2.95 --make  -O2 -fvia-C -funbox-strict-fields )
>
>what can I do to a) work around this, b) help finding/fixing the reason?
>--
>-- Johannes Waldmann ---- http://www.informatik.uni-leipzig.de/~joe/ --
>-- joe@informatik.uni-leipzig.de -- phone/fax (+49) 341 9732 204/209 --
>
>_______________________________________________
>Glasgow-haskell-users mailing list
>Glasgow-haskell-users@haskell.org
>http://www.haskell.org/mailman/listinfo/glasgow-haskell-users
>

*********************************************************************
*  Andrew Cheadle                    email:  a.cheadle@doc.ic.ac.uk *
*  Department of Computing           http://www.doc.ic.ac.uk/~amc4/ *
*  Imperial College                                                 *
*  University of London                                             *
*********************************************************************