[mpich-discuss] MPI_Alloc_mem: optimized memory usage

[Rajeev Thakur]

Yes, it is useful for MPI-2 one-sided communication, but perhaps less useful
for send-recv.

Rajeev 

> -----Original Message-----
> From: mpich-discuss-bounces at mcs.anl.gov 
> [mailto:mpich-discuss-bounces at mcs.anl.gov] On Behalf Of James S Perrin
> Sent: Monday, November 10, 2008 5:24 AM
> To: mpich-discuss at mcs.anl.gov
> Subject: Re: [mpich-discuss] MPI_Alloc_mem: optimized memory usage
> 
> Thanks for the info Rajeev. Would this be something worth 
> looking at in 
> future releases in the nemesis channel as we run more systems 
> with more 
> and more cores per node?
> 
> Regards
> James
> 
> Rajeev Thakur wrote:
> > In the sshm channel (scalable shared memory), which is now 
> deprecated,
> > Alloc_mem allocated shared memory for use in one-sided 
> communication. I
> > believe in other cases at present, Alloc_mem just calls malloc.
> > 
> > Rajeev 
> > 
> >> -----Original Message-----
> >> From: mpich-discuss-bounces at mcs.anl.gov 
> >> [mailto:mpich-discuss-bounces at mcs.anl.gov] On Behalf Of 
> James S Perrin
> >> Sent: Friday, November 07, 2008 11:55 AM
> >> To: mpich
> >> Subject: [mpich-discuss] MPI_Alloc_mem: optimized memory usage
> >>
> >> Hi,
> >> 	Are MPICH2 calls optimized for SMP/multi-core 
> >> architectures if I 
> >> allocate buffers using MPI_Alloc_mem()? I was reading the in 
> >> the MPI2.1 
> >> spec that MPI_Alloc_mem can be implemented to take advantage 
> >> of shared 
> >> memory pools when available meaning I can keep my code 
> portable and 
> >> clean. Presumably this would only be available in ch3:ssm 
> and nemesis 
> >> channels.
> >>
> >> Regards
> >> James
> > 
> 
> -- 
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