September 2012 - mpiwg-rma - mailman3.cels.anl.gov

Re: [Mpi3-rma] Target displacement sign issue
by Hubert Ritzdorf 04 Sep '12

04 Sep '12

Hi, Possibly another solution: (*) Let MPI_AINT_MAX the maximal value of MPI_Aint variable (*) Let the window_base of a window created by MPI_WIN_CREATE_DYNAMIC be MPI_AINT_MAX + 1 (*) Define a new function MPI_Get_address_dynamic returning the address of a location relative to MPI_AINT_MAX + 1 (*) Remove the non-negative qualification in the description of target_disp in MPI_{Put/Get/Accumulate/...). Hubert > -----Original Message----- > From: mpi3-rma-bounces(a)lists.mpi-forum.org [mailto:mpi3-rma- > bounces(a)lists.mpi-forum.org] On Behalf Of Hubert Ritzdorf > Sent: Tuesday, September 04, 2012 7:23 PM > To: MPI 3.0 Remote Memory Access working group > Subject: Re: [Mpi3-rma] Target displacement sign issue > > Hi, > > MPI_Get_address returns an MPI_Aint which is signed.(integer). > > C: > MPI_Aint's may be used in Reduce Operations with Min/Max > or the application can internally use min/max computations. > Can anybody guarantee that applications don't perform > min/max operations on these displacements (which results in different > results for unsigned and signed variables) or use derived values of these > displacements in other signed/unsigned significant cases. > > Fortran: > MPI_BOTTOM is a variable in a common block/module. Thus, > MPI_Get_address might really return a signed integer (depending on the > compiler). > Fortran doesn't have unsigned integers and cannot handle them. > Thus, the non-negative integer specification for target_disp in > MPI_{Put/Get/Accumulate/...) > might be incorrect for Fortran and MPI_Win_Create_dynamic(). > > Hubert > ________________________________________ > From: mpi3-rma-bounces(a)lists.mpi-forum.org [mpi3-rma-bounces(a)lists.mpi- > forum.org] on behalf of Jim Dinan [dinan(a)mcs.anl.gov] > Sent: Tuesday, September 04, 2012 5:10 PM > To: mpi3-rma(a)lists.mpi-forum.org > Subject: Re: [Mpi3-rma] Target displacement sign issue > > Hi All, > > This is an important issue that we need to resolve before releasing the > 3.0 spec. Please take a look and send feedback. > > Dave has voiced a concern that the implicit type conversion in my > proposed text below may not be portable. If anyone has more experience > with this aspect (signed->unsigned conversion) of C/Fortran/etc type > systems, please chime in. > > ~Jim. > > On 8/28/12 2:29 PM, Jim Dinan wrote: > > Hi All, > > > > Here is the suggested change to address this issue. In the paragraph on > > page 425, line 1, add the bracketed sentence: > > > > In the case of a window created with MPI_WIN_CREATE_DYNAMIC, the > > target_disp for all RMA functions is the address at the target; i.e., > > the effective window_base is MPI_BOTTOM and the disp_unit is one. [Thus, > > for dynamic windows, the target_disp argument to all RMA functions in > > interpreted as unsigned.] Users should use MPI_GET_ADDRESS at the target > > process to determine the address of a target memory location and > > communicate this address to the origin process. > > > > ~Jim. > > > > On 8/28/12 9:46 AM, Jim Dinan wrote: > >> Hi All, > >> > >> Currently, target displacements in put/get/acc/etc are defined to be > >> non-negative integers of type, MPI_Aint. MPI_Aint is defined to be a > >> signed integer. However, displacements associated with dynamic windows > >> are addresses (unsigned) and can range into the space of negative > >> integers. > >> > >> It seems like the least impact change would be to add a special case > >> that the displacement argument will be interpreted as unsigned for > >> dynamic windows. Changing the interface to take an 'unsigned MPI_Aint' > >> would be the most clear (and preserve the existing and intended new > >> semantics), but would break backward compatibility. > >> > >> Interested to hear your thoughts. > >> > >> ~Jim. > _______________________________________________ > mpi3-rma mailing list > mpi3-rma(a)lists.mpi-forum.org > http://lists.mpi-forum.org/mailman/listinfo.cgi/mpi3-rma > > > Click > https://www.mailcontrol.com/sr/O6SiJI5AP4bTndxI!oX7Up2F0f+S6NySj!qlvEoKFyZ > NTFyVkk9WjRzJbmnfHdyw83VGVWKbSfC8ewgPpp7kgg== to report this email as > spam. > > _______________________________________________ > mpi3-rma mailing list > mpi3-rma(a)lists.mpi-forum.org > http://lists.mpi-forum.org/mailman/listinfo.cgi/mpi3-rma

1 0

Re: [Mpi3-rma] Fwd: [Mpi-comments] Freeing memory allocated in MPI_WIN_ALLOCATE_SHARED
by Jeff Hammond 04 Sep '12

04 Sep '12

Okay, I thought it might do that but despite having a paper copy of the MPI-3 RMA chapter three feet from me at the time, I was too lazy to look it up. Thanks for the clarification. Jeff On Tue, Sep 4, 2012 at 11:47 PM, Jim Dinan <dinan(a)mcs.anl.gov> wrote: > MPI_Win_free also frees memory allocated by MPI_Win_allocate. > > ~Jim. > > > On 9/4/12 4:22 PM, Jeff Hammond wrote: >> >> Shouldn't that be a new call (MPI_Win_free_shared) to keep the usage >> of MPI_Win_free uniform? MPI_Win_free doesn't deallocate the buffers >> in any other situation, does it? >> >> Jeff >> >> On Tue, Sep 4, 2012 at 4:07 PM, Jim Dinan <dinan(a)mcs.anl.gov> wrote: >>> >>> Hi All, >>> >>> It looks like we forgot to include the text specifying that >>> MPI_Win_allocate_shared memory is freed along with the window. >>> >>> ~Jim. >>> >>> >>> -------- Original Message -------- >>> Subject: [Mpi-comments] Freeing memory allocated in >>> MPI_WIN_ALLOCATE_SHARED >>> Date: Tue, 4 Sep 2012 12:49:10 +0000 >>> From: Hubert Ritzdorf <Hubert.Ritzdorf(a)emea.nec.com> >>> Reply-To: Comments on the MPI Standard >>> <mpi-comments(a)lists.mpi-forum.org> >>> To: mpi-comments(a)lists.mpi-forum.org >>> <mpi-comments(a)lists.mpi-forum.org> >>> >>> >>> >>> Hi, >>> >>> is it correct that MPI_Win_free should free the memory allocated in >>> MPI_Win_allocate_shared ? >>> >>> MPI_Win_free (Page 416, Line 5-6) specifies this only for >>> memory allocated by MPI_Win_allocate. >>> I think that an additional reference to MPI_Win_allocate_shared is >>> missing also on Page 420, Line 31, Page 448 Line 25, Page 609 Line 31, >>> Page 613 Line 1, Page 614 Line 9, Page 614 Line 31. >>> >>> Hubert >>> >>> >>> >>> >>> >>> _______________________________________________ >>> mpi3-rma mailing list >>> mpi3-rma(a)lists.mpi-forum.org >>> http://lists.mpi-forum.org/mailman/listinfo.cgi/mpi3-rma >> >> >> >> > _______________________________________________ > mpi3-rma mailing list > mpi3-rma(a)lists.mpi-forum.org > http://lists.mpi-forum.org/mailman/listinfo.cgi/mpi3-rma -- Jeff Hammond Argonne Leadership Computing Facility University of Chicago Computation Institute jhammond(a)alcf.anl.gov / (630) 252-5381 http://www.linkedin.com/in/jeffhammond https://wiki.alcf.anl.gov/parts/index.php/User:Jhammond

1 0

Re: [Mpi3-rma] Fwd: [Mpi-comments] Freeing memory allocated in MPI_WIN_ALLOCATE_SHARED
by Jim Dinan 04 Sep '12

04 Sep '12

MPI_Win_free also frees memory allocated by MPI_Win_allocate. ~Jim. On 9/4/12 4:22 PM, Jeff Hammond wrote: > Shouldn't that be a new call (MPI_Win_free_shared) to keep the usage > of MPI_Win_free uniform? MPI_Win_free doesn't deallocate the buffers > in any other situation, does it? > > Jeff > > On Tue, Sep 4, 2012 at 4:07 PM, Jim Dinan <dinan(a)mcs.anl.gov> wrote: >> Hi All, >> >> It looks like we forgot to include the text specifying that >> MPI_Win_allocate_shared memory is freed along with the window. >> >> ~Jim. >> >> >> -------- Original Message -------- >> Subject: [Mpi-comments] Freeing memory allocated in >> MPI_WIN_ALLOCATE_SHARED >> Date: Tue, 4 Sep 2012 12:49:10 +0000 >> From: Hubert Ritzdorf <Hubert.Ritzdorf(a)emea.nec.com> >> Reply-To: Comments on the MPI Standard >> <mpi-comments(a)lists.mpi-forum.org> >> To: mpi-comments(a)lists.mpi-forum.org <mpi-comments(a)lists.mpi-forum.org> >> >> >> >> Hi, >> >> is it correct that MPI_Win_free should free the memory allocated in >> MPI_Win_allocate_shared ? >> >> MPI_Win_free (Page 416, Line 5-6) specifies this only for >> memory allocated by MPI_Win_allocate. >> I think that an additional reference to MPI_Win_allocate_shared is >> missing also on Page 420, Line 31, Page 448 Line 25, Page 609 Line 31, >> Page 613 Line 1, Page 614 Line 9, Page 614 Line 31. >> >> Hubert >> >> >> >> >> >> _______________________________________________ >> mpi3-rma mailing list >> mpi3-rma(a)lists.mpi-forum.org >> http://lists.mpi-forum.org/mailman/listinfo.cgi/mpi3-rma > > >

1 0

Re: [Mpi3-rma] Fwd: [Mpi-comments] Freeing memory allocated in MPI_WIN_ALLOCATE_SHARED
by Jeff Hammond 04 Sep '12

04 Sep '12

Shouldn't that be a new call (MPI_Win_free_shared) to keep the usage of MPI_Win_free uniform? MPI_Win_free doesn't deallocate the buffers in any other situation, does it? Jeff On Tue, Sep 4, 2012 at 4:07 PM, Jim Dinan <dinan(a)mcs.anl.gov> wrote: > Hi All, > > It looks like we forgot to include the text specifying that > MPI_Win_allocate_shared memory is freed along with the window. > > ~Jim. > > > -------- Original Message -------- > Subject: [Mpi-comments] Freeing memory allocated in > MPI_WIN_ALLOCATE_SHARED > Date: Tue, 4 Sep 2012 12:49:10 +0000 > From: Hubert Ritzdorf <Hubert.Ritzdorf(a)emea.nec.com> > Reply-To: Comments on the MPI Standard > <mpi-comments(a)lists.mpi-forum.org> > To: mpi-comments(a)lists.mpi-forum.org <mpi-comments(a)lists.mpi-forum.org> > > > > Hi, > > is it correct that MPI_Win_free should free the memory allocated in > MPI_Win_allocate_shared ? > > MPI_Win_free (Page 416, Line 5-6) specifies this only for > memory allocated by MPI_Win_allocate. > I think that an additional reference to MPI_Win_allocate_shared is > missing also on Page 420, Line 31, Page 448 Line 25, Page 609 Line 31, > Page 613 Line 1, Page 614 Line 9, Page 614 Line 31. > > Hubert > > > > > > _______________________________________________ > mpi3-rma mailing list > mpi3-rma(a)lists.mpi-forum.org > http://lists.mpi-forum.org/mailman/listinfo.cgi/mpi3-rma -- Jeff Hammond Argonne Leadership Computing Facility University of Chicago Computation Institute jhammond(a)alcf.anl.gov / (630) 252-5381 http://www.linkedin.com/in/jeffhammond https://wiki.alcf.anl.gov/parts/index.php/User:Jhammond

1 0

Re: [Mpi3-rma] Target displacement sign issue
by Hubert Ritzdorf 04 Sep '12

04 Sep '12

Hi, MPI_Get_address returns an MPI_Aint which is signed.(integer). C: MPI_Aint's may be used in Reduce Operations with Min/Max or the application can internally use min/max computations. Can anybody guarantee that applications don't perform min/max operations on these displacements (which results in different results for unsigned and signed variables) or use derived values of these displacements in other signed/unsigned significant cases. Fortran: MPI_BOTTOM is a variable in a common block/module. Thus, MPI_Get_address might really return a signed integer (depending on the compiler). Fortran doesn't have unsigned integers and cannot handle them. Thus, the non-negative integer specification for target_disp in MPI_{Put/Get/Accumulate/...) might be incorrect for Fortran and MPI_Win_Create_dynamic(). Hubert ________________________________________ From: mpi3-rma-bounces(a)lists.mpi-forum.org [mpi3-rma-bounces(a)lists.mpi-forum.org] on behalf of Jim Dinan [dinan(a)mcs.anl.gov] Sent: Tuesday, September 04, 2012 5:10 PM To: mpi3-rma(a)lists.mpi-forum.org Subject: Re: [Mpi3-rma] Target displacement sign issue Hi All, This is an important issue that we need to resolve before releasing the 3.0 spec. Please take a look and send feedback. Dave has voiced a concern that the implicit type conversion in my proposed text below may not be portable. If anyone has more experience with this aspect (signed->unsigned conversion) of C/Fortran/etc type systems, please chime in. ~Jim. On 8/28/12 2:29 PM, Jim Dinan wrote: > Hi All, > > Here is the suggested change to address this issue. In the paragraph on > page 425, line 1, add the bracketed sentence: > > In the case of a window created with MPI_WIN_CREATE_DYNAMIC, the > target_disp for all RMA functions is the address at the target; i.e., > the effective window_base is MPI_BOTTOM and the disp_unit is one. [Thus, > for dynamic windows, the target_disp argument to all RMA functions in > interpreted as unsigned.] Users should use MPI_GET_ADDRESS at the target > process to determine the address of a target memory location and > communicate this address to the origin process. > > ~Jim. > > On 8/28/12 9:46 AM, Jim Dinan wrote: >> Hi All, >> >> Currently, target displacements in put/get/acc/etc are defined to be >> non-negative integers of type, MPI_Aint. MPI_Aint is defined to be a >> signed integer. However, displacements associated with dynamic windows >> are addresses (unsigned) and can range into the space of negative >> integers. >> >> It seems like the least impact change would be to add a special case >> that the displacement argument will be interpreted as unsigned for >> dynamic windows. Changing the interface to take an 'unsigned MPI_Aint' >> would be the most clear (and preserve the existing and intended new >> semantics), but would break backward compatibility. >> >> Interested to hear your thoughts. >> >> ~Jim. _______________________________________________ mpi3-rma mailing list mpi3-rma(a)lists.mpi-forum.org http://lists.mpi-forum.org/mailman/listinfo.cgi/mpi3-rma Click https://www.mailcontrol.com/sr/O6SiJI5AP4bTndxI!oX7Up2F0f+S6NySj!qlvEoKFyZN… to report this email as spam.

1 0

Re: [Mpi3-rma] Target displacement sign issue
by Jim Dinan 04 Sep '12

04 Sep '12

Hi All, This is an important issue that we need to resolve before releasing the 3.0 spec. Please take a look and send feedback. Dave has voiced a concern that the implicit type conversion in my proposed text below may not be portable. If anyone has more experience with this aspect (signed->unsigned conversion) of C/Fortran/etc type systems, please chime in. ~Jim. On 8/28/12 2:29 PM, Jim Dinan wrote: > Hi All, > > Here is the suggested change to address this issue. In the paragraph on > page 425, line 1, add the bracketed sentence: > > In the case of a window created with MPI_WIN_CREATE_DYNAMIC, the > target_disp for all RMA functions is the address at the target; i.e., > the effective window_base is MPI_BOTTOM and the disp_unit is one. [Thus, > for dynamic windows, the target_disp argument to all RMA functions in > interpreted as unsigned.] Users should use MPI_GET_ADDRESS at the target > process to determine the address of a target memory location and > communicate this address to the origin process. > > ~Jim. > > On 8/28/12 9:46 AM, Jim Dinan wrote: >> Hi All, >> >> Currently, target displacements in put/get/acc/etc are defined to be >> non-negative integers of type, MPI_Aint. MPI_Aint is defined to be a >> signed integer. However, displacements associated with dynamic windows >> are addresses (unsigned) and can range into the space of negative >> integers. >> >> It seems like the least impact change would be to add a special case >> that the displacement argument will be interpreted as unsigned for >> dynamic windows. Changing the interface to take an 'unsigned MPI_Aint' >> would be the most clear (and preserve the existing and intended new >> semantics), but would break backward compatibility. >> >> Interested to hear your thoughts. >> >> ~Jim.

1 0

[Mpi3-rma] Fwd: [Mpi-comments] Freeing memory allocated in MPI_WIN_ALLOCATE_SHARED
by Jim Dinan 04 Sep '12

04 Sep '12

Hi All, It looks like we forgot to include the text specifying that MPI_Win_allocate_shared memory is freed along with the window. ~Jim. -------- Original Message -------- Subject: [Mpi-comments] Freeing memory allocated in MPI_WIN_ALLOCATE_SHARED Date: Tue, 4 Sep 2012 12:49:10 +0000 From: Hubert Ritzdorf <Hubert.Ritzdorf(a)emea.nec.com> Reply-To: Comments on the MPI Standard <mpi-comments(a)lists.mpi-forum.org> To: mpi-comments(a)lists.mpi-forum.org <mpi-comments(a)lists.mpi-forum.org> Hi, is it correct that MPI_Win_free should free the memory allocated in MPI_Win_allocate_shared ? MPI_Win_free (Page 416, Line 5-6) specifies this only for memory allocated by MPI_Win_allocate. I think that an additional reference to MPI_Win_allocate_shared is missing also on Page 420, Line 31, Page 448 Line 25, Page 609 Line 31, Page 613 Line 1, Page 614 Line 9, Page 614 Line 31. Hubert

1 0