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Subject: Re: [OMPI devel] [EXTERNAL] non-blocking collectives, SPARC, and alignment
From: Eugene Loh (eugene.loh_at_[hidden])
Date: 2012-07-18 13:28:18

I put back r26802, modifying nbc_internal.h and nbc.c. Can you add this
to your omnibus v1.7 CMR 3169? I left the padding/packing alone and
simply replaced round-schedule accesses with macros that handle the
addressing and use memcpy for data movement. The former simplifies the
pointer manipulation and the latter helps portability. Specifically,
NBC now works on SPARC.

On 7/16/2012 1:45 PM, Barrett, Brian W wrote:
> It's unlikely that I will have time to fix this in the short term. The
> scheduling code is fairly localized in nbc.c if Oracle has some time to
> spend looking at these issues. If not, it might be best to remove the
> libnbc code from 1.7, as it's unfortunately clear that it's not as ready
> for integration as we believed and I don't have time to fix the code base.
> On 7/16/12 2:50 PM, "Eugene Loh"<eugene.loh_at_[hidden]> wrote:
>> The NBC functionality doesn't fare very well on SPARC. One of the
>> problems is with data alignment. An NBC schedule is a number of
>> variously sized fields laid out contiguously in linear memory (e.g.,
>> see nbc_internal.h or nbc.c) and words don't have much natural
>> alignment.