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Re: [Mpi3-bwcompat] Are we presenting MPI_COUNT in Stuttgart?
by unknown＠example.com 10 Sep '10

10 Sep '10

Jeff Squyres wrote on Fri, 10 Sep 2010 at 07:50:39 > I am here, but I would need some review in order to be able to discuss > it intelligently. Ok, thanks for volunteering. :P The ticket should be pretty straight forward. It's still not complete with respect to the examples, but all the functions are done. Most of it is pretty boring, really, the most interesting changes are actually around the pack/unpack/size routines, where we've changed the definition of the position parameter. What's the process for tickets - I was anticipating a first reading at the October meeting, assuming that the ticket has to be complete before being presented to the forum. But if we can get things moving along sooner rather than later, that would be great. I'm also hoping to have a reference implementation by the October meeting. Enjoy Stuttgart! -Fab > > > On Sep 10, 2010, at 4:22 PM, Solt, David George wrote: > >> Anyone knowledgeable of the ticket going to be there? (I will not) >> Dave >> >> -----Original Message----- From: mpi3-bwcompat-bounces_at_[hidden] >> [mailto:mpi3-bwcompat- bounces_at_[hidden]] On Behalf Of Jeff Squyres >> Sent: Friday, September 10, 2010 4:21 AM To: MPI-3 backwards >> compatability WG Subject: [Mpi3-bwcompat] Are we presenting MPI_COUNT >> in Stuttgart? >> >> Fab did all this great work on the ticket - is someone presenting it in >> Stuttgart next week? >> >> -- >> Jeff Squyres >> jsquyres_at_[hidden] >> For corporate legal information go to: >> http://www.cisco.com/web/about/doing_business/legal/cri/ >> >> >> _______________________________________________ >> Mpi3-bwcompat mailing list >> Mpi3-bwcompat_at_[hidden] >> http://lists.mpi-forum.org/mailman/listinfo.cgi/mpi3-bwcompat >> >> _______________________________________________ >> Mpi3-bwcompat mailing list >> Mpi3-bwcompat_at_[hidden] >> http://lists.mpi-forum.org/mailman/listinfo.cgi/mpi3-bwcompat > >

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Re: [Mpi3-bwcompat] Are we presenting MPI_COUNT in Stuttgart?
by unknown＠example.com 10 Sep '10

10 Sep '10

I am here, but I would need some review in order to be able to discuss it intelligently. On Sep 10, 2010, at 4:22 PM, Solt, David George wrote: > Anyone knowledgeable of the ticket going to be there? (I will not) > Dave > > -----Original Message----- > From: mpi3-bwcompat-bounces_at_[hidden] [mailto:mpi3-bwcompat-bounces_at_[hidden]] On Behalf Of Jeff Squyres > Sent: Friday, September 10, 2010 4:21 AM > To: MPI-3 backwards compatability WG > Subject: [Mpi3-bwcompat] Are we presenting MPI_COUNT in Stuttgart? > > Fab did all this great work on the ticket - is someone presenting it in Stuttgart next week? > > -- > Jeff Squyres > jsquyres_at_[hidden] > For corporate legal information go to: > http://www.cisco.com/web/about/doing_business/legal/cri/ > > > _______________________________________________ > Mpi3-bwcompat mailing list > Mpi3-bwcompat_at_[hidden] > http://lists.mpi-forum.org/mailman/listinfo.cgi/mpi3-bwcompat > > _______________________________________________ > Mpi3-bwcompat mailing list > Mpi3-bwcompat_at_[hidden] > http://lists.mpi-forum.org/mailman/listinfo.cgi/mpi3-bwcompat -- Jeff Squyres jsquyres_at_[hidden] For corporate legal information go to: http://www.cisco.com/web/about/doing_business/legal/cri/

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Re: [Mpi3-bwcompat] Are we presenting MPI_COUNT in Stuttgart?
by unknown＠example.com 10 Sep '10

10 Sep '10

Anyone knowledgeable of the ticket going to be there? (I will not) Dave -----Original Message----- From: mpi3-bwcompat-bounces_at_[hidden] [mailto:mpi3-bwcompat-bounces_at_[hidden]] On Behalf Of Jeff Squyres Sent: Friday, September 10, 2010 4:21 AM To: MPI-3 backwards compatability WG Subject: [Mpi3-bwcompat] Are we presenting MPI_COUNT in Stuttgart? Fab did all this great work on the ticket - is someone presenting it in Stuttgart next week? -- Jeff Squyres jsquyres_at_[hidden] For corporate legal information go to: http://www.cisco.com/web/about/doing_business/legal/cri/ _______________________________________________ Mpi3-bwcompat mailing list Mpi3-bwcompat_at_[hidden] http://lists.mpi-forum.org/mailman/listinfo.cgi/mpi3-bwcompat

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Are we presenting MPI_COUNT in Stuttgart?
by unknown＠example.com 10 Sep '10

10 Sep '10

Fab did all this great work on the ticket - is someone presenting it in Stuttgart next week? -- Jeff Squyres jsquyres_at_[hidden] For corporate legal information go to: http://www.cisco.com/web/about/doing_business/legal/cri/

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Re: [Mpi3-bwcompat] Anyone joining the call?
by unknown＠example.com 03 Sep '10

03 Sep '10

Sorry Jeff, I sent out a cancellation earlier this week as I am in training, but I did not cancel the outlook meeting. Dave -----Original Message----- From: mpi3-bwcompat-bounces_at_[hidden] [mailto:mpi3-bwcompat-bounces_at_[hidden]] On Behalf Of Jeff Squyres Sent: Friday, September 03, 2010 12:11 PM To: MPI-3 backwards compatability WG Subject: Re: [Mpi3-bwcompat] Anyone joining the call? I applied the school bus stop rule: I waited for 10 minutes and the bus didn't show up, so I don't have to go to school today. On Sep 3, 2010, at 1:07 PM, Jeff Squyres wrote: > We're supposed to have a call right now, right? > > I'm sitting on the bridge, "The leader has not yet arrived..." > > -- > Jeff Squyres > jsquyres_at_[hidden] > For corporate legal information go to: > http://www.cisco.com/web/about/doing_business/legal/cri/ > > _______________________________________________ > Mpi3-bwcompat mailing list > Mpi3-bwcompat_at_[hidden] > http://lists.mpi-forum.org/mailman/listinfo.cgi/mpi3-bwcompat -- Jeff Squyres jsquyres_at_[hidden] For corporate legal information go to: http://www.cisco.com/web/about/doing_business/legal/cri/ _______________________________________________ Mpi3-bwcompat mailing list Mpi3-bwcompat_at_[hidden] http://lists.mpi-forum.org/mailman/listinfo.cgi/mpi3-bwcompat

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Re: [Mpi3-bwcompat] Anyone joining the call?
by unknown＠example.com 03 Sep '10

03 Sep '10

I applied the school bus stop rule: I waited for 10 minutes and the bus didn't show up, so I don't have to go to school today. On Sep 3, 2010, at 1:07 PM, Jeff Squyres wrote: > We're supposed to have a call right now, right? > > I'm sitting on the bridge, "The leader has not yet arrived..." > > -- > Jeff Squyres > jsquyres_at_[hidden] > For corporate legal information go to: > http://www.cisco.com/web/about/doing_business/legal/cri/ > > _______________________________________________ > Mpi3-bwcompat mailing list > Mpi3-bwcompat_at_[hidden] > http://lists.mpi-forum.org/mailman/listinfo.cgi/mpi3-bwcompat -- Jeff Squyres jsquyres_at_[hidden] For corporate legal information go to: http://www.cisco.com/web/about/doing_business/legal/cri/

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Anyone joining the call?
by unknown＠example.com 03 Sep '10

03 Sep '10

We're supposed to have a call right now, right? I'm sitting on the bridge, "The leader has not yet arrived..." -- Jeff Squyres jsquyres_at_[hidden] For corporate legal information go to: http://www.cisco.com/web/about/doing_business/legal/cri/

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Re: [Mpi3-bwcompat] Ticked 224 updated
by unknown＠example.com 06 Aug '10

06 Aug '10

I reviewed the examples in the following chapters and there are no changes needed. All the examples either used a constant for the count or did not show the declaration of the variable used for count: 8. MPI Environmental Management 9. The Info Object 10. Process Creation and Management 11. One-sided communication 12. External Interfaces Dave -----Original Message----- From: mpi3-bwcompat-bounces_at_[hidden] [mailto:mpi3-bwcompat-bounces_at_[hidden]] On Behalf Of Fab Tillier Sent: Friday, August 06, 2010 1:55 PM To: MPI-3 backwards compatability WG Subject: [Mpi3-bwcompat] Ticked 224 updated Hi Folks, I've updated ticket 224. I had apparently tackled some of the examples but not updated the ticket. At this point, I believe all the APIs are covered and updated. Let me know if there are any that you see that I've missed. Cheers, -Fab _______________________________________________ Mpi3-bwcompat mailing list Mpi3-bwcompat_at_[hidden] http://lists.mpi-forum.org/mailman/listinfo.cgi/mpi3-bwcompat

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Ticked 224 updated
by unknown＠example.com 06 Aug '10

06 Aug '10

Hi Folks, I've updated ticket 224. I had apparently tackled some of the examples but not updated the ticket. At this point, I believe all the APIs are covered and updated. Let me know if there are any that you see that I've missed. Cheers, -Fab

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Re: [Mpi3-bwcompat] Meeting notes from 7/23
by unknown＠example.com 23 Jul '10

23 Jul '10

If you couldn't tell from the notes, this was quite a lively meeting. :-) On Jul 23, 2010, at 6:03 PM, Solt, David George wrote: > Also available on https://svn.mpi-forum.org/trac/mpi-forum-web/wiki/BackCompatMeetings > > Discussion was around the continued effort around MPI_Count. The latest effort (#224) is a re-work of an early 2.2 proposal to introduce MPI_Count but allow implementations to define MPI_Count to be an int in order to retain backward compatibility. Fabian has been working through some of the details, and there are a few "boundary" cases where MPI_Count interfaces with other concepts. In particular MPI_Pack which currently looks like this: > > int MPI_Pack(void* inbuf, int incount, MPI_Datatype datatype, void* outbuf, int outsize, int *position, MPI_Comm comm) > > This API uses outsize and position, neither of which are well-defined as either an int or an MPI_Count. Several ideas were discussed around making one or other of outsize and position one of the following: MPI_Count, size_t, uint64, MPI_Aint, MPI_Size, MPI_Position. We wrestled with the exact meaning of "what is a position" and how does it relate to other uses of MPI_Aint, etc. We discussed whether there needs to be a distinction between the size of an "offset" in memory vs. within a message vs. within a file. (Notetaker's note: MPI_Offset is generally used for file positions, MPI_Aint for memory positions and MPI_Count is proposed to address positions within a message) > > MPI_Pack ties several of these concepts together because MPI_Pack creates something in memory but is also intended to be used as a message or could be used in a file operation. The "result" of MPI_Pack is currently an int (position) which represents a position in memory (therefore should have been MPI_Aint) but is used roughly as a message count in sends/recvs (thus MPI_Count). The number of bytes which can be packed can exceed the size of MPI_Count and thus could force us to make requirements about the relative sizes of MPI_Aint and MPI_Count. We did not want to do that. In the end we agreed that position, which is currently defined as "current position in buffer, in bytes" should be re-defined as a "current count of MPI_PACKED datatypes within the buffer" (something like that) and therefore can be an MPI_Count. This means that MPI_Pack is now restricted to working with buffers which are only capable of being "indexed" with MPI_Count values. The argument really represents t! > he position within a buffer, but we have re-framed it in this way to avoid introducing a new type and to ensure that position will be something we can pass as an MPI_Count to communication routines. Another option we considered here was using MPI_Offset for the position argument -- because that's pretty much what it is: an offset. But we can't do that for two reasons: 1) it would break backwards compatibility (because MPI_Offset != int in many current MPI implementations), and 2) you can't pass an MPI_Offset to the count argument of MPI_Send. We will add some text explaining that MPI_Pack is not intended to pack extremely large buffers and that extremely large messages should be pipe-lined with multiple MPI_Pack/MPI_Send operations for performance reasons. > > The outsize argument, on the other hand, cannot as easily be converted to an MPI_Count argument. We could say that the position is always in terms of how many counts of MPI_BYTE's would fit into the buffer, but that is a contorted use of MPI_Count. So, we proposed to introduce MPI_Size for use as the outsize argument to MPI_Pack/MPI_Unpack. We did not discuss it much, but I believe it will also get used for MPI_Type_size. Another option we considered here was using MPI_Offset for the position argument -- because that's pretty much what it is: an offset. But we can't do that for two reasons: 1) it would break backwards compatibility (because MPI_Offset != int in many current MPI implementations), and 2) you can't pass an MPI_Offset to the count argument of MPI_Send. MPI_Size will not need to be tied in any way to the size of MPI_Count. If on a system, MPI_Count is smaller than MPI_Size, it only means that we can pass in very large buffers to MPI_Pack, but not very large count! > s. If MPI_Count is larger than MPI_Size, it means that we may not be able to pack as large a message as we can send directly with communication routines. > > Agreed on a schedule for the next 2 weeks in which Fab will update the ticket based on today's discussion and the other attendees are encouraged to start dividing up the chapters to search for example code which should be changed to reflect the changes being proposed. > > The plan is to polish off ticket #224 and have an implementation for the October, 2010 meeting. > > _______________________________________________ > Mpi3-bwcompat mailing list > Mpi3-bwcompat_at_[hidden] > http://lists.mpi-forum.org/mailman/listinfo.cgi/mpi3-bwcompat > -- Jeff Squyres jsquyres_at_[hidden] For corporate legal information go to: http://www.cisco.com/web/about/doing_business/legal/cri/

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