- mpiwg-p2p - mailman3.cels.anl.gov

Re: [mpiwg-p2p] Message matching for tools
by George Bosilca 09 Feb '16

09 Feb '16

Sorry to jump in the middle (or the end) of the discussion. From my "MPI user" point of view, the last part of the proposed advice is unsettling. "The usage of some info hints may allow the MPI library to change its behavior and, as a result, impact the effectiveness of tools." seems to have a broader scope, and includes application developers, when the most obvious target should have been tools developers. I think removing the last part and emphasizing tools and libraries, makes a more clear point. "Setting info hints on the predefined communicators \const{MPI\_COMM\_WORLD } and \const{MPI\_COMM\_SELF} may have unintended effects, as changes to these global objects may affect all components of the application, including libraries and tools." George. On Tue, Feb 9, 2016 at 8:02 PM, Jim Dinan <james.dinan(a)gmail.com> wrote: > We're calling the proposal "info assertions", but the standard still > refers to them as "hints". > > Reading the proposed change again, I think it might be helpful (and more > fair to tools) to say why info could impact tools: > > Setting info hints on the predefined communicators \const{MPI\_COMM\_WORLD > } and \const{MPI\_COMM\_SELF} may have unintended effects, as changes to > these global objects may affect all components of the application, > including libraries. The usage of some info hints may allow the MPI > library to change its behavior and, as a result, impact the effectiveness > of tools. > > ~Jim. > > On Tue, Feb 9, 2016 at 12:38 PM, Daniel Holmes <dholmes(a)epcc.ed.ac.uk> > wrote: > >> Hi Jim, >> >> I like that change. On a side note: are we really still calling them >> "info hints" in this context rather than "info assertions"? >> >> Cheers, >> Dan. >> >> >> On 09/02/2016 15:51, Jim Dinan wrote: >> >> Hi All, >> >> I'm preparing the updated draft of info assertions for a reading in >> March. Where did we land on an advice regarding tools? Do we want advice >> (1) to users, that they info keys may impact tools and/or (2) to tools that >> they should check info? >> >> For instance, we could extend the current advice with the following >> sentence: >> >> Setting info hints on the predefined communicators \const{MPI\_COMM\_ >> WORLD} and \const{MPI\_COMM\_SELF} may have unintended effects, as >> changes to these global objects may affect all components of the >> application, including libraries. The usage of info hints may also >> impact the effectiveness of tools. >> >> ~Jim. >> >> On Fri, Dec 18, 2015 at 5:24 AM, Marc-Andre Hermanns < >> <hermanns(a)jara.rwth-aachen.de>hermanns(a)jara.rwth-aachen.de> wrote: >> >>> Hi Jeff, >>> >>> > at the moment we don't handle MPI_THREAD_MULTIPLE at all. But we >>> want >>> > to get there ;-) >>> > >>> > >>> > You should vote for endpoints, as this may help you out here, >>> > particularly if users start mapping endpoints 1:1 w/ threads. >>> >>> That would certainly ease things for us in these situations. >>> Unfortunately endpoints force use to adapt other infrastructure in our >>> measurement system. >>> >>> > b) Creating a derived datatype on the fly to add tool-level data to >>> > the original payload may induce a large overhead in practically >>> > _every_ send & receive operation and perturb the measurement. >>> > >>> > >>> > You should evaluate this experimentally. I wrote a simple test >>> > ( >>> https://github.com/jeffhammond/BigMPI/blob/master/test/perf/typepiggy.c) >>> > and measured 1.5 us per call of overhead to create a datatype. That >>> > is not significant except for very small messages. >>> >>> Thanks for the pointer. You are right. I should evaluate this further. >>> 1.5us does indeed seem tolerable. I wonder how the influence of the >>> derived datatype is on overall messaging performance, though. >>> >>> This is also something I should evaluate in the process. >>> >>> Cheers, >>> Marc-Andre >>> >>> -- >>> Marc-Andre Hermanns >>> Jülich Aachen Research Alliance, >>> High Performance Computing (JARA-HPC) >>> Jülich Supercomputing Centre (JSC) >>> >>> Schinkelstrasse 2 >>> 52062 Aachen >>> Germany >>> >>> Phone: +49 2461 61 2509 | +49 241 80 24381 >>> Fax: +49 2461 80 6 99753 >>> www.jara.org/jara-hpc >>> email: hermanns(a)jara.rwth-aachen.de >>> >>> >>> _______________________________________________ >>> mpiwg-p2p mailing list >>> mpiwg-p2p(a)lists.mpi-forum.org >>> http://lists.mpi-forum.org/mailman/listinfo.cgi/mpiwg-p2p >>> >> >> >> >> _______________________________________________ >> mpiwg-p2p mailing [email protected]://lists.mpi-forum.org/mailman/listinfo.cgi/mpiwg-p2p >> >> >> -- >> Dan Holmes >> Applications Consultant in HPC Research >> EPCC, The University of Edinburgh >> James Clerk Maxwell Building >> The Kings Buildings >> Peter Guthrie Tait Road >> Edinburgh >> EH9 3FD >> T: +44(0)131 651 3465 >> E: dholmes(a)epcc.ed.ac.uk >> >> *Please consider the environment before printing this email.* >> >> >> The University of Edinburgh is a charitable body, registered in >> Scotland, with registration number SC005336. >> >> _______________________________________________ >> mpiwg-p2p mailing list >> mpiwg-p2p(a)lists.mpi-forum.org >> http://lists.mpi-forum.org/mailman/listinfo.cgi/mpiwg-p2p >> > > > _______________________________________________ > mpiwg-p2p mailing list > mpiwg-p2p(a)lists.mpi-forum.org > http://lists.mpi-forum.org/mailman/listinfo.cgi/mpiwg-p2p >

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Info assertions draft
by Jim Dinan 09 Feb '16

09 Feb '16

Hi All, I have attached an updated draft for the info assertions proposal. The two week deadline is quickly approaching; please send feedback before the end of the week. Thanks, ~Jim.

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Re: [mpiwg-p2p] Message matching for tools
by Jim Dinan 09 Feb '16

09 Feb '16

We're calling the proposal "info assertions", but the standard still refers to them as "hints". Reading the proposed change again, I think it might be helpful (and more fair to tools) to say why info could impact tools: Setting info hints on the predefined communicators \const{MPI\_COMM\_WORLD} and \const{MPI\_COMM\_SELF} may have unintended effects, as changes to these global objects may affect all components of the application, including libraries. The usage of some info hints may allow the MPI library to change its behavior and, as a result, impact the effectiveness of tools. ~Jim. On Tue, Feb 9, 2016 at 12:38 PM, Daniel Holmes <dholmes(a)epcc.ed.ac.uk> wrote: > Hi Jim, > > I like that change. On a side note: are we really still calling them "info > hints" in this context rather than "info assertions"? > > Cheers, > Dan. > > > On 09/02/2016 15:51, Jim Dinan wrote: > > Hi All, > > I'm preparing the updated draft of info assertions for a reading in > March. Where did we land on an advice regarding tools? Do we want advice > (1) to users, that they info keys may impact tools and/or (2) to tools that > they should check info? > > For instance, we could extend the current advice with the following > sentence: > > Setting info hints on the predefined communicators \const{MPI\_COMM\_WORLD > } and \const{MPI\_COMM\_SELF} may have unintended effects, as changes to > these global objects may affect all components of the application, > including libraries. The usage of info hints may also impact the > effectiveness of tools. > > ~Jim. > > On Fri, Dec 18, 2015 at 5:24 AM, Marc-Andre Hermanns < > <hermanns(a)jara.rwth-aachen.de>hermanns(a)jara.rwth-aachen.de> wrote: > >> Hi Jeff, >> >> > at the moment we don't handle MPI_THREAD_MULTIPLE at all. But we >> want >> > to get there ;-) >> > >> > >> > You should vote for endpoints, as this may help you out here, >> > particularly if users start mapping endpoints 1:1 w/ threads. >> >> That would certainly ease things for us in these situations. >> Unfortunately endpoints force use to adapt other infrastructure in our >> measurement system. >> >> > b) Creating a derived datatype on the fly to add tool-level data to >> > the original payload may induce a large overhead in practically >> > _every_ send & receive operation and perturb the measurement. >> > >> > >> > You should evaluate this experimentally. I wrote a simple test >> > ( >> https://github.com/jeffhammond/BigMPI/blob/master/test/perf/typepiggy.c) >> > and measured 1.5 us per call of overhead to create a datatype. That >> > is not significant except for very small messages. >> >> Thanks for the pointer. You are right. I should evaluate this further. >> 1.5us does indeed seem tolerable. I wonder how the influence of the >> derived datatype is on overall messaging performance, though. >> >> This is also something I should evaluate in the process. >> >> Cheers, >> Marc-Andre >> >> -- >> Marc-Andre Hermanns >> Jülich Aachen Research Alliance, >> High Performance Computing (JARA-HPC) >> Jülich Supercomputing Centre (JSC) >> >> Schinkelstrasse 2 >> 52062 Aachen >> Germany >> >> Phone: +49 2461 61 2509 | +49 241 80 24381 >> Fax: +49 2461 80 6 99753 >> www.jara.org/jara-hpc >> email: hermanns(a)jara.rwth-aachen.de >> >> >> _______________________________________________ >> mpiwg-p2p mailing list >> mpiwg-p2p(a)lists.mpi-forum.org >> http://lists.mpi-forum.org/mailman/listinfo.cgi/mpiwg-p2p >> > > > > _______________________________________________ > mpiwg-p2p mailing [email protected]://lists.mpi-forum.org/mailman/listinfo.cgi/mpiwg-p2p > > > -- > Dan Holmes > Applications Consultant in HPC Research > EPCC, The University of Edinburgh > James Clerk Maxwell Building > The Kings Buildings > Peter Guthrie Tait Road > Edinburgh > EH9 3FD > T: +44(0)131 651 3465 > E: dholmes(a)epcc.ed.ac.uk > > *Please consider the environment before printing this email.* > > > The University of Edinburgh is a charitable body, registered in > Scotland, with registration number SC005336. > > _______________________________________________ > mpiwg-p2p mailing list > mpiwg-p2p(a)lists.mpi-forum.org > http://lists.mpi-forum.org/mailman/listinfo.cgi/mpiwg-p2p >

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Re: [mpiwg-p2p] Message matching for tools
by Daniel Holmes 09 Feb '16

09 Feb '16

Hi Jim, I like that change. On a side note: are we really still calling them "info hints" in this context rather than "info assertions"? Cheers, Dan. On 09/02/2016 15:51, Jim Dinan wrote: > Hi All, > > I'm preparing the updated draft of info assertions for a reading in > March. Where did we land on an advice regarding tools? Do we want > advice (1) to users, that they info keys may impact tools and/or (2) > to tools that they should check info? > > For instance, we could extend the current advice with the following > sentence: > > Setting info hints on the predefined communicators > \const{MPI\_COMM\_WORLD} and \const{MPI\_COMM\_SELF}may have > unintended effects, as changes to these global objects may affect all > components of the application, including libraries. The usage of info > hints may also impact the effectiveness of tools. > > ~Jim. > > On Fri, Dec 18, 2015 at 5:24 AM, Marc-Andre Hermanns > <hermanns(a)jara.rwth-aachen.de <mailto:[email protected]>> > wrote: > > Hi Jeff, > > > at the moment we don't handle MPI_THREAD_MULTIPLE at all. > But we want > > to get there ;-) > > > > > > You should vote for endpoints, as this may help you out here, > > particularly if users start mapping endpoints 1:1 w/ threads. > > That would certainly ease things for us in these situations. > Unfortunately endpoints force use to adapt other infrastructure in our > measurement system. > > > b) Creating a derived datatype on the fly to add tool-level > data to > > the original payload may induce a large overhead in practically > > _every_ send & receive operation and perturb the measurement. > > > > > > You should evaluate this experimentally. I wrote a simple test > > > (https://github.com/jeffhammond/BigMPI/blob/master/test/perf/typepiggy.c) > > and measured 1.5 us per call of overhead to create a datatype. That > > is not significant except for very small messages. > > Thanks for the pointer. You are right. I should evaluate this further. > 1.5us does indeed seem tolerable. I wonder how the influence of the > derived datatype is on overall messaging performance, though. > > This is also something I should evaluate in the process. > > Cheers, > Marc-Andre > > -- > Marc-Andre Hermanns > Jï¿½lich Aachen Research Alliance, > High Performance Computing (JARA-HPC) > Jï¿½lich Supercomputing Centre (JSC) > > Schinkelstrasse 2 > 52062 Aachen > Germany > > Phone: +49 2461 61 2509 <tel:%2B49%202461%2061%202509> | +49 241 > 80 24381 <tel:%2B49%20241%2080%2024381> > Fax: +49 2461 80 6 99753 <tel:%2B49%202461%2080%206%2099753> > www.jara.org/jara-hpc <http://www.jara.org/jara-hpc> > email: hermanns(a)jara.rwth-aachen.de > <mailto:[email protected]> > > > _______________________________________________ > mpiwg-p2p mailing list > mpiwg-p2p(a)lists.mpi-forum.org <mailto:[email protected]> > http://lists.mpi-forum.org/mailman/listinfo.cgi/mpiwg-p2p > > > > > _______________________________________________ > mpiwg-p2p mailing list > mpiwg-p2p(a)lists.mpi-forum.org > http://lists.mpi-forum.org/mailman/listinfo.cgi/mpiwg-p2p -- Dan Holmes Applications Consultant in HPC Research EPCC, The University of Edinburgh James Clerk Maxwell Building The Kings Buildings Peter Guthrie Tait Road Edinburgh EH9 3FD T: +44(0)131 651 3465 E: dholmes(a)epcc.ed.ac.uk *Please consider the environment before printing this email.* The University of Edinburgh is a charitable body, registered in Scotland, with registration number SC005336.

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Re: [mpiwg-p2p] Message matching for tools
by Jim Dinan 09 Feb '16

09 Feb '16

Hi All, I'm preparing the updated draft of info assertions for a reading in March. Where did we land on an advice regarding tools? Do we want advice (1) to users, that they info keys may impact tools and/or (2) to tools that they should check info? For instance, we could extend the current advice with the following sentence: Setting info hints on the predefined communicators \const{MPI\_COMM\_WORLD} and \const{MPI\_COMM\_SELF} may have unintended effects, as changes to these global objects may affect all components of the application, including libraries. The usage of info hints may also impact the effectiveness of tools. ~Jim. On Fri, Dec 18, 2015 at 5:24 AM, Marc-Andre Hermanns < hermanns(a)jara.rwth-aachen.de> wrote: > Hi Jeff, > > > at the moment we don't handle MPI_THREAD_MULTIPLE at all. But we want > > to get there ;-) > > > > > > You should vote for endpoints, as this may help you out here, > > particularly if users start mapping endpoints 1:1 w/ threads. > > That would certainly ease things for us in these situations. > Unfortunately endpoints force use to adapt other infrastructure in our > measurement system. > > > b) Creating a derived datatype on the fly to add tool-level data to > > the original payload may induce a large overhead in practically > > _every_ send & receive operation and perturb the measurement. > > > > > > You should evaluate this experimentally. I wrote a simple test > > (https://github.com/jeffhammond/BigMPI/blob/master/test/perf/typepiggy.c > ) > > and measured 1.5 us per call of overhead to create a datatype. That > > is not significant except for very small messages. > > Thanks for the pointer. You are right. I should evaluate this further. > 1.5us does indeed seem tolerable. I wonder how the influence of the > derived datatype is on overall messaging performance, though. > > This is also something I should evaluate in the process. > > Cheers, > Marc-Andre > > -- > Marc-Andre Hermanns > Jülich Aachen Research Alliance, > High Performance Computing (JARA-HPC) > Jülich Supercomputing Centre (JSC) > > Schinkelstrasse 2 > 52062 Aachen > Germany > > Phone: +49 2461 61 2509 | +49 241 80 24381 > Fax: +49 2461 80 6 99753 > www.jara.org/jara-hpc > email: hermanns(a)jara.rwth-aachen.de > > > _______________________________________________ > mpiwg-p2p mailing list > mpiwg-p2p(a)lists.mpi-forum.org > http://lists.mpi-forum.org/mailman/listinfo.cgi/mpiwg-p2p >

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Re: [mpiwg-p2p] Next meeting: TODAY at 11am US Central
by Daniel Holmes 01 Feb '16

01 Feb '16

Hi all, Meeting notes (with actions) now up on the wiki at: https://github.com/mpiwg-p2p/p2p-issues/wiki/notes-2016-02-01 Cheers, Dan. On 01/02/2016 13:19, Daniel Holmes wrote: > Hi all, > > The next teleconference will be today at 11am US Central time via > webex. Connection information can be found on the wiki page at: > https://github.com/mpiwg-p2p/p2p-issues/wiki > > Agenda: > 1) Discuss and agree text changes for issue #26 "deprecate send cancel" > 2) Update status for issue #11 "info assertions" > 3) Update status for issue #32 "allocating receive and freeing send" > > I'd like to get all three of these issues ready for reading/voting in > time for the next meeting. Today is 2 weeks before the 2 week > deadline, i.e. this is final meeting with time after it to take action > before the cut-off for the next face-to-face meeting. > > Cheers, > Dan. > -- Dan Holmes Applications Consultant in HPC Research EPCC, The University of Edinburgh James Clerk Maxwell Building The Kings Buildings Peter Guthrie Tait Road Edinburgh EH9 3FD T: +44(0)131 651 3465 E: dholmes(a)epcc.ed.ac.uk *Please consider the environment before printing this email.* The University of Edinburgh is a charitable body, registered in Scotland, with registration number SC005336.

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Re: [mpiwg-p2p] Next meeting: TODAY at 11am US Central
by Kenneth Raffenetti 01 Feb '16

01 Feb '16

I'll be joining late after attending an interview seminar. Ken On 02/01/2016 09:12 AM, Jim Dinan wrote: > Oh, sorry, you said that already. Nice agenda. See you in a couple > hours. :) > > ~Jim. > > On Mon, Feb 1, 2016 at 10:12 AM, Jim Dinan <james.dinan(a)gmail.com > <mailto:[email protected]>> wrote: > > I propose that we also review the info assertions changes to make > sure it's ready for a reading in Chicago. > > ~Jim. > > On Mon, Feb 1, 2016 at 8:19 AM, Daniel Holmes <dholmes(a)epcc.ed.ac.uk > <mailto:[email protected]>> wrote: > > Hi all, > > The next teleconference will be today at 11am US Central time > via webex. Connection information can be found on the wiki page at: > https://github.com/mpiwg-p2p/p2p-issues/wiki > > Agenda: > 1) Discuss and agree text changes for issue #26 "deprecate send > cancel" > 2) Update status for issue #11 "info assertions" > 3) Update status for issue #32 "allocating receive and freeing send" > > I'd like to get all three of these issues ready for > reading/voting in time for the next meeting. Today is 2 weeks > before the 2 week deadline, i.e. this is final meeting with time > after it to take action before the cut-off for the next > face-to-face meeting. > > Cheers, > Dan. > > -- > Dan Holmes > Applications Consultant in HPC Research > EPCC, The University of Edinburgh > James Clerk Maxwell Building > The Kings Buildings > Peter Guthrie Tait Road > Edinburgh > EH9 3FD > T: +44(0)131 651 3465 <tel:%2B44%280%29131%20651%203465> > E: dholmes(a)epcc.ed.ac.uk <mailto:[email protected]> > > *Please consider the environment before printing this email.* > > > The University of Edinburgh is a charitable body, registered in > Scotland, with registration number SC005336. > > _______________________________________________ > mpiwg-p2p mailing list > mpiwg-p2p(a)lists.mpi-forum.org <mailto:[email protected]> > http://lists.mpi-forum.org/mailman/listinfo.cgi/mpiwg-p2p > > > > > > _______________________________________________ > mpiwg-p2p mailing list > mpiwg-p2p(a)lists.mpi-forum.org > http://lists.mpi-forum.org/mailman/listinfo.cgi/mpiwg-p2p >

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Re: [mpiwg-p2p] Next meeting: TODAY at 11am US Central
by Jim Dinan 01 Feb '16

01 Feb '16

Oh, sorry, you said that already. Nice agenda. See you in a couple hours. :) ~Jim. On Mon, Feb 1, 2016 at 10:12 AM, Jim Dinan <james.dinan(a)gmail.com> wrote: > I propose that we also review the info assertions changes to make sure > it's ready for a reading in Chicago. > > ~Jim. > > On Mon, Feb 1, 2016 at 8:19 AM, Daniel Holmes <dholmes(a)epcc.ed.ac.uk> > wrote: > >> Hi all, >> >> The next teleconference will be today at 11am US Central time via webex. >> Connection information can be found on the wiki page at: >> https://github.com/mpiwg-p2p/p2p-issues/wiki >> >> Agenda: >> 1) Discuss and agree text changes for issue #26 "deprecate send cancel" >> 2) Update status for issue #11 "info assertions" >> 3) Update status for issue #32 "allocating receive and freeing send" >> >> I'd like to get all three of these issues ready for reading/voting in >> time for the next meeting. Today is 2 weeks before the 2 week deadline, >> i.e. this is final meeting with time after it to take action before the >> cut-off for the next face-to-face meeting. >> >> Cheers, >> Dan. >> >> -- >> Dan Holmes >> Applications Consultant in HPC Research >> EPCC, The University of Edinburgh >> James Clerk Maxwell Building >> The Kings Buildings >> Peter Guthrie Tait Road >> Edinburgh >> EH9 3FD >> T: +44(0)131 651 3465 >> E: dholmes(a)epcc.ed.ac.uk >> >> *Please consider the environment before printing this email.* >> >> >> The University of Edinburgh is a charitable body, registered in >> Scotland, with registration number SC005336. >> >> _______________________________________________ >> mpiwg-p2p mailing list >> mpiwg-p2p(a)lists.mpi-forum.org >> http://lists.mpi-forum.org/mailman/listinfo.cgi/mpiwg-p2p >> > >

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Re: [mpiwg-p2p] Next meeting: TODAY at 11am US Central
by Jim Dinan 01 Feb '16

01 Feb '16

I propose that we also review the info assertions changes to make sure it's ready for a reading in Chicago. ~Jim. On Mon, Feb 1, 2016 at 8:19 AM, Daniel Holmes <dholmes(a)epcc.ed.ac.uk> wrote: > Hi all, > > The next teleconference will be today at 11am US Central time via webex. > Connection information can be found on the wiki page at: > https://github.com/mpiwg-p2p/p2p-issues/wiki > > Agenda: > 1) Discuss and agree text changes for issue #26 "deprecate send cancel" > 2) Update status for issue #11 "info assertions" > 3) Update status for issue #32 "allocating receive and freeing send" > > I'd like to get all three of these issues ready for reading/voting in time > for the next meeting. Today is 2 weeks before the 2 week deadline, i.e. > this is final meeting with time after it to take action before the cut-off > for the next face-to-face meeting. > > Cheers, > Dan. > > -- > Dan Holmes > Applications Consultant in HPC Research > EPCC, The University of Edinburgh > James Clerk Maxwell Building > The Kings Buildings > Peter Guthrie Tait Road > Edinburgh > EH9 3FD > T: +44(0)131 651 3465 > E: dholmes(a)epcc.ed.ac.uk > > *Please consider the environment before printing this email.* > > > The University of Edinburgh is a charitable body, registered in > Scotland, with registration number SC005336. > > _______________________________________________ > mpiwg-p2p mailing list > mpiwg-p2p(a)lists.mpi-forum.org > http://lists.mpi-forum.org/mailman/listinfo.cgi/mpiwg-p2p >

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Next meeting: TODAY at 11am US Central
by Daniel Holmes 01 Feb '16

01 Feb '16

Hi all, The next teleconference will be today at 11am US Central time via webex. Connection information can be found on the wiki page at: https://github.com/mpiwg-p2p/p2p-issues/wiki Agenda: 1) Discuss and agree text changes for issue #26 "deprecate send cancel" 2) Update status for issue #11 "info assertions" 3) Update status for issue #32 "allocating receive and freeing send" I'd like to get all three of these issues ready for reading/voting in time for the next meeting. Today is 2 weeks before the 2 week deadline, i.e. this is final meeting with time after it to take action before the cut-off for the next face-to-face meeting. Cheers, Dan. -- Dan Holmes Applications Consultant in HPC Research EPCC, The University of Edinburgh James Clerk Maxwell Building The Kings Buildings Peter Guthrie Tait Road Edinburgh EH9 3FD T: +44(0)131 651 3465 E: dholmes(a)epcc.ed.ac.uk *Please consider the environment before printing this email.* The University of Edinburgh is a charitable body, registered in Scotland, with registration number SC005336.

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