That is because it scales itself to the number of available msg queues.
So with Nadia's patch there are more and it runs slower.
In fact it seems to start one process per message queue, so perhaps it's
just running out of processes or something. Ok it should not segfault.
BTW a great way to debug slab corruptions with LTP faster is to run with
a slab thrasher stress module like http://firstfloor.org/~andi/crasher-26.diff
-Andi
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