Messages in this thread | | | Date | Mon, 31 May 2010 22:39:37 -0400 (EDT) | From | Mikulas Patocka <> | Subject | Re: [dm-devel] [PATCH] DM-CRYPT: Scale to multiple CPUs |
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> > >> 2) Per volume threads and mempools were added to solve low memory > > >> problems (exhausted mempools), isn't now possible deadlock here again? > > > > > > Increasing the number of parallel submitters does not increase deadlocks > > > with mempool as long as they don't nest. They would just > > > block each other, but eventually make progress as one finishes. > > > > I mean if they nest of course, sorry for confusion. > > No change to that, it's the same as it always worked. > > Anyways, Right now you would need to nest more than 16 times I think > to exhaust the mempool (or 8, but the pages are less critical I think) > > For me that seems like a "don't do that if hurts" situation.
If the mempools are per-instance (they are), it can nest any number of times, because each nested instance will get new mempools. It is not a problem.
Mikulas
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