Messages in this thread | | | From | Nick Piggin <> | Subject | Re: [ofa-general] Re: [patch 5/6] mmu_notifier: Support for drivers with revers maps (f.e. for XPmem) | Date | Tue, 26 Feb 2008 19:52:41 +1100 |
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On Tuesday 26 February 2008 18:21, Gleb Natapov wrote: > On Tue, Feb 26, 2008 at 05:11:32PM +1100, Nick Piggin wrote: > > > You are missing one point here. The MPI specifications that have > > > been out there for decades do not require the process use a library > > > for allocating the buffer. I realize that is a horrible shortcoming, > > > but that is the world we live in. Even if we could change that spec, > > > > Can you change the spec? > > Not really. It will break all existing codes.
I meant as in eg. submit changes to MPI-3
> MPI-2 provides a call for > memory allocation (and it's beneficial to use this call for some > interconnects), but many (most?) applications are still written for MPI-1 > and those that are written for MPI-2 mostly uses the old habit of > allocating memory by malloc(), or even use stack or BSS memory for > communication buffer purposes.
OK, so MPI-2 already has some way to do that... I'm not saying that we can now completely dismiss the idea of using notifiers for this, but it is just a good data point to know.
Thanks, Nick
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