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Re: [Mpi3-bwcompat] Ticket 265 ready for review
by unknown＠example.com 26 Jan '11

26 Jan '11

OK, thanks for the explanation. If count is encapsulated in derived datatypes, we might need new datatype constructor functions that take MPI_Count, or at least a new MPI_Type_contiguous. Let's say the user wants to send an array of size X integers, where X is some weird number greater than 2G. If there is a new Type_contiguous, we have to see how it affects Type_get_envelope and Type_get_contents. Rajeev On Jan 26, 2011, at 4:56 PM, Fab Tillier wrote: > Hi Rajeev, > > Rajeev Thakur wrote on Wed, 26 Jan 2011 at 14:31:06 > >> I wasn't at the last Forum meeting, so may have missed some of the >> background. >> >> Is ticket #224 obsolete now? If so, you may want to indicate that in 224. > > Sorry, I've resolved it as withdrawn, with a comment that it was supersceded by 265. > >> Do MPI_Send/Recv etc. remain unchanged, i.e., no MPI_Count in them? If >> so, why do we need a new MPI_Get_count? > > MPI_Send/Recv remain unchanged, and users are expected to create derived datatypes to express data structures that are larger than 2^31 basic elements. Now that you point it out, though, I would think MPI_Get_elements is sufficient, as MPI_Get_count should be using the same datatype as used in the operation that transferred the data. Hoping that Jeff, Quincy, or David can chime in here and clarify why we need it. > >> Are the new "w" versions of the collectives specifically related to >> this ticket (i.e. to address the 64-bit count requirement) or are they >> a separate issue (i.e. a general need for array of datatypes instead of >> one datatype)? > > By addressing the need for large counts via derived datatypes, we effectively encapsulate the 'count' in the 'datatype' parameters. As an example, if you want to gather different 'counts' from different ranks where there is no common denominator, you would need to derive a datatype for each source rank, and specify those individual datatypes. That can't be done today, we can only specify different counts, but are limited by the 2^31 range of the count fields. So the missing 'w' functions allow the datatype to be used to encapsulate the count. > >> Minor typos: Two of the prototypes for Scatterw say Scatterv instead. > > Fixed, thanks. > > -Fab > >> >> Rajeev >> >> >> >> >> On Jan 26, 2011, at 3:38 PM, Fab Tillier wrote: >> >>> Ok folks, not a whole lot of time before the meeting, so it would be >> great if we could get everyone to read through the ticket and make sure >> I didn't miss something. I'd like to have David Solt generate a PDF >> sometime next week, in time for me to read it at the forum the >> following week (our time slot for this is 'working lunch' on Tuesday. >>> >>> https://svn.mpi-forum.org/trac/mpi-forum-web/ticket/265 >>> >>> Thanks for your help, >>> -Fab >>> >>> _______________________________________________ >>> 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 > > _______________________________________________ > 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] Ticket 265 ready for review
by unknown＠example.com 26 Jan '11

26 Jan '11

Geoffrey Paulsen wrote on Wed, 26 Jan 2011 at 14:32:55 > I reviewed this document and I found two type-o's: > > 1) MPI_Scatterw - two of the function prototypes that was cut and paste > from MPI_Scatterv didn't have the v changed to w. > > 2) MPI_Iallgatherw - page 192, line 48, needs to have an "MPI_I" > prepended to "Allgatherw" at the very beginning of that section. Fixed, thanks! -Fab > -----Original Message----- > From: Fab Tillier > Sent: Wednesday, January 26, 2011 3:39 PM > > Ok folks, not a whole lot of time before the meeting, so it would be > great if we could get everyone to read through the ticket and make sure > I didn't miss something. I'd like to have David Solt generate a PDF > sometime next week, in time for me to read it at the forum the following > week (our time slot for this is 'working lunch' on Tuesday. > > https://svn.mpi-forum.org/trac/mpi-forum-web/ticket/265 > > Thanks for your help, > -Fab

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Re: [Mpi3-bwcompat] Ticket 265 ready for review
by unknown＠example.com 26 Jan '11

26 Jan '11

Hi Rajeev, Rajeev Thakur wrote on Wed, 26 Jan 2011 at 14:31:06 > I wasn't at the last Forum meeting, so may have missed some of the > background. > > Is ticket #224 obsolete now? If so, you may want to indicate that in 224. Sorry, I've resolved it as withdrawn, with a comment that it was supersceded by 265. > Do MPI_Send/Recv etc. remain unchanged, i.e., no MPI_Count in them? If > so, why do we need a new MPI_Get_count? MPI_Send/Recv remain unchanged, and users are expected to create derived datatypes to express data structures that are larger than 2^31 basic elements. Now that you point it out, though, I would think MPI_Get_elements is sufficient, as MPI_Get_count should be using the same datatype as used in the operation that transferred the data. Hoping that Jeff, Quincy, or David can chime in here and clarify why we need it. > Are the new "w" versions of the collectives specifically related to > this ticket (i.e. to address the 64-bit count requirement) or are they > a separate issue (i.e. a general need for array of datatypes instead of > one datatype)? By addressing the need for large counts via derived datatypes, we effectively encapsulate the 'count' in the 'datatype' parameters. As an example, if you want to gather different 'counts' from different ranks where there is no common denominator, you would need to derive a datatype for each source rank, and specify those individual datatypes. That can't be done today, we can only specify different counts, but are limited by the 2^31 range of the count fields. So the missing 'w' functions allow the datatype to be used to encapsulate the count. > Minor typos: Two of the prototypes for Scatterw say Scatterv instead. Fixed, thanks. -Fab > > Rajeev > > > > > On Jan 26, 2011, at 3:38 PM, Fab Tillier wrote: > >> Ok folks, not a whole lot of time before the meeting, so it would be > great if we could get everyone to read through the ticket and make sure > I didn't miss something. I'd like to have David Solt generate a PDF > sometime next week, in time for me to read it at the forum the > following week (our time slot for this is 'working lunch' on Tuesday. >> >> https://svn.mpi-forum.org/trac/mpi-forum-web/ticket/265 >> >> Thanks for your help, >> -Fab >> >> _______________________________________________ >> 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] Ticket 265 ready for review
by unknown＠example.com 26 Jan '11

26 Jan '11

I reviewed this document and I found two type-o's: 1) MPI_Scatterw - two of the function prototypes that was cut and paste from MPI_Scatterv didn't have the v changed to w. 2) MPI_Iallgatherw - page 192, line 48, needs to have an "MPI_I" prepended to "Allgatherw" at the very beginning of that section. -----Original Message----- From: mpi3-bwcompat-bounces_at_[hidden] [mailto:mpi3-bwcompat-bounces_at_[hidden]] On Behalf Of Fab Tillier Sent: Wednesday, January 26, 2011 3:39 PM To: MPI-3 backwards compatability WG Subject: [Mpi3-bwcompat] Ticket 265 ready for review Ok folks, not a whole lot of time before the meeting, so it would be great if we could get everyone to read through the ticket and make sure I didn't miss something. I'd like to have David Solt generate a PDF sometime next week, in time for me to read it at the forum the following week (our time slot for this is 'working lunch' on Tuesday. https://svn.mpi-forum.org/trac/mpi-forum-web/ticket/265 Thanks for your help, -Fab _______________________________________________ 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] Ticket 265 ready for review
by unknown＠example.com 26 Jan '11

26 Jan '11

I wasn't at the last Forum meeting, so may have missed some of the background. Is ticket #224 obsolete now? If so, you may want to indicate that in 224. Do MPI_Send/Recv etc. remain unchanged, i.e., no MPI_Count in them? If so, why do we need a new MPI_Get_count? Are the new "w" versions of the collectives specifically related to this ticket (i.e. to address the 64-bit count requirement) or are they a separate issue (i.e. a general need for array of datatypes instead of one datatype)? Minor typos: Two of the prototypes for Scatterw say Scatterv instead. Rajeev On Jan 26, 2011, at 3:38 PM, Fab Tillier wrote: > Ok folks, not a whole lot of time before the meeting, so it would be great if we could get everyone to read through the ticket and make sure I didn't miss something. I'd like to have David Solt generate a PDF sometime next week, in time for me to read it at the forum the following week (our time slot for this is 'working lunch' on Tuesday. > > https://svn.mpi-forum.org/trac/mpi-forum-web/ticket/265 > > Thanks for your help, > -Fab > > _______________________________________________ > Mpi3-bwcompat mailing list > Mpi3-bwcompat_at_[hidden] > http://lists.mpi-forum.org/mailman/listinfo.cgi/mpi3-bwcompat

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Ticket 265 ready for review
by unknown＠example.com 26 Jan '11

26 Jan '11

Ok folks, not a whole lot of time before the meeting, so it would be great if we could get everyone to read through the ticket and make sure I didn't miss something. I'd like to have David Solt generate a PDF sometime next week, in time for me to read it at the forum the following week (our time slot for this is 'working lunch' on Tuesday. https://svn.mpi-forum.org/trac/mpi-forum-web/ticket/265 Thanks for your help, -Fab

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Hot off the press, ticket 265
by unknown＠example.com 21 Jan '11

21 Jan '11

Hey folks, I've started on the (hopefully) last ticket to add support for large counts. It's not finished, but thought I'd send this out to show folks what I'm doing and get comments early if I'm doing something horrendous. https://svn.mpi-forum.org/trac/mpi-forum-web/ticket/265 -Fab

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Re: [Mpi3-bwcompat] Mtg today?
by unknown＠example.com 21 Jan '11

21 Jan '11

Quincey Koziol wrote on Fri, 21 Jan 2011 at 10:37:23 > On Jan 21, 2011, at 12:02 PM, Fab Tillier wrote: > >> I am expecting so, though am woefully unprepared... How fast two >> weeks go by. > > I was hoping to call in, but a previous meeting overran its > schedule by ~30 minutes. :-/ > > Fab - you asked me to work on something at the last forum > meeting, but I've forgotten what that was now. Can you refresh my > memory, so I can get it done? You were going to create a new ticket to extend the datatype creation functions to take MPI_Count as input, so that creating large datatypes is easier for your code. I would recommend showing your use case, to help explain why creating a bunch of smaller datatypes is nasty. -Fab > > Thanks, > Quincey > > >> >> -----Original Message----- >> From: mpi3-bwcompat-bounces_at_[hidden] [mailto:mpi3- > bwcompat-bounces_at_[hidden]] On Behalf Of Jeff Squyres > (jsquyres) >> Sent: Friday, January 21, 2011 9:46 AM >> To: MPI-3 Backwards Compat WG >> Subject: [Mpi3-bwcompat] Mtg today? >> >> >> >> Sent from my PDA. No type good. >> _______________________________________________ >> 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 > > > _______________________________________________ > 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] Mtg today?
by unknown＠example.com 21 Jan '11

21 Jan '11

On Jan 21, 2011, at 12:02 PM, Fab Tillier wrote: > I am expecting so, though am woefully unprepared... How fast two weeks go by. I was hoping to call in, but a previous meeting overran its schedule by ~30 minutes. :-/ Fab - you asked me to work on something at the last forum meeting, but I've forgotten what that was now. Can you refresh my memory, so I can get it done? Thanks, Quincey > > -----Original Message----- > From: mpi3-bwcompat-bounces_at_[hidden] [mailto:mpi3-bwcompat-bounces_at_[hidden]] On Behalf Of Jeff Squyres (jsquyres) > Sent: Friday, January 21, 2011 9:46 AM > To: MPI-3 Backwards Compat WG > Subject: [Mpi3-bwcompat] Mtg today? > > > > Sent from my PDA. No type good. > _______________________________________________ > 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] Mtg today?
by unknown＠example.com 21 Jan '11

21 Jan '11

I am expecting so, though am woefully unprepared... How fast two weeks go by. -----Original Message----- From: mpi3-bwcompat-bounces_at_[hidden] [mailto:mpi3-bwcompat-bounces_at_[hidden]] On Behalf Of Jeff Squyres (jsquyres) Sent: Friday, January 21, 2011 9:46 AM To: MPI-3 Backwards Compat WG Subject: [Mpi3-bwcompat] Mtg today? Sent from my PDA. No type good. _______________________________________________ Mpi3-bwcompat mailing list Mpi3-bwcompat_at_[hidden] http://lists.mpi-forum.org/mailman/listinfo.cgi/mpi3-bwcompat

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