Re: [OMPI users] ompe support for filesystems
Gilles,
Thank you for replying.
I took a look at the code and am curious to understand where the actual
read/write/seek etc. operations are implemented. From what I can
see/understand - what you pointed me to implements file open/close
etc. operations that pertain to particular filesystems.
I then tried to figure out the read/write/seek etc. operations and can
see that a MPI_File structure appears to have a f_io_selected_module
member, whose v_2_0_0 member seems to have the list of pointers to all
the functionals dealing with the actual file write/read/seek
functionality. Is this correct?
What I would like to figure out is where the actual writes or reads
happen (as in the underlying filesystem's implementations). I imagine
for some filesystems a write, for example, is not just a simple call to
the write onto disk but involves a bit more logic/magic.
Thanks!
Ognen
Gilles Gouaillardet via users writes:
> Hi Ognen,
>
> MPI-IO is implemented by two components:
> - ROMIO (from MPICH)
> - ompio ("native" Open MPI MPI-IO, default component unless running on
> Lustre)
>
> Assuming you want to add support for a new filesystem in ompio, first
> step is to implement a new component in the fs framework
> the framework is in /ompi/mca/fs, and each component is in its own
> directory (for example ompi/mca/fs/gpfs)
>
> There are a some configury tricks (create a configure.m4, add Makefile
> to autoconf, ...) to make sure your component is even compiled.
> If you are struggling with these, feel free to open a Pull Request to
> get some help fixing the missing bits.
>
> Cheers,
>
> Gilles
>
> On Sun, Nov 1, 2020 at 12:18 PM Ognen Duzlevski via users
> wrote:
>>
>> Hello!
>>
>> If I wanted to support a specific filesystem in open mpi, how is this
>> done? What code in the source tree does it?
>>
>> Thanks!
>> Ognen
Re: [OMPI users] Starting a mixed fortran python MPMD application
Afraid I would have no idea - all I could tell them is that there was a bug and it has been fixed On Nov 2, 2020, at 12:18 AM, Andrea Piacentini via users mailto:users@lists.open-mpi.org> > wrote: I installed version 4.0.5 and the problem appears to be fixed. Can you please help us explaining it to our users pointing to the commit (at least to the first release tag) solving this issue? Thank you very much Andrea Piacentini -- Andrea Piacentini piacentini.p...@gmail.com Tel. +39/3356007579 skype: andrea3.14
Re: [OMPI users] ompe support for filesystems
the ompio software infrastructure has multiple frameworks.
fs framework: abstracts out file system level operations (open, close, etc)
fbtl framework: provides the abstractions and implementations of *individual*
file I/O operations (seek,read,write, iread,iwrite)
fcoll framework: provides the abstractions and implementations of *collective*
file I/O operations ( read_all, write_all, etc.)
sharedfp framework: provides the abstractions and implementations *shared file
pointer* file I/O operations (read_shared, write_shared, read_ordered,
write_ordered).
Feel free to ping me also directly if you need more assistance. If you are
looking for a reference and more explanations, please have a look at the
following paper:
Mohamad Chaarawi, Edgar Gabriel, Rainer Keller, Richard Graham, George Bosilca
and Jack Dongarra, 'OMPIO: A Modular Software Architecture for MPI I/O', in Y.
Cotronis, A. Danalis, D. Nikolopoulos, J. Dongarra, (Eds.) 'Recent Advances in
Message Passing Interface', LNCS vol. 6960, pp. 81-89, Springer, 2011.
http://www2.cs.uh.edu/~gabriel/publications/EuroMPI11_OMPIO.pdf
Best regards
Edgar
-Original Message-
From: users On Behalf Of Ognen Duzlevski via
users
Sent: Monday, November 2, 2020 7:54 AM
To: Open MPI Users
Cc: Ognen Duzlevski
Subject: Re: [OMPI users] ompe support for filesystems
Gilles,
Thank you for replying.
I took a look at the code and am curious to understand where the actual
read/write/seek etc. operations are implemented. From what I can see/understand
- what you pointed me to implements file open/close etc. operations that
pertain to particular filesystems.
I then tried to figure out the read/write/seek etc. operations and can see that
a MPI_File structure appears to have a f_io_selected_module member, whose
v_2_0_0 member seems to have the list of pointers to all the functionals
dealing with the actual file write/read/seek functionality. Is this correct?
What I would like to figure out is where the actual writes or reads happen (as
in the underlying filesystem's implementations). I imagine for some filesystems
a write, for example, is not just a simple call to the write onto disk but
involves a bit more logic/magic.
Thanks!
Ognen
Gilles Gouaillardet via users writes:
> Hi Ognen,
>
> MPI-IO is implemented by two components:
> - ROMIO (from MPICH)
> - ompio ("native" Open MPI MPI-IO, default component unless running
> on Lustre)
>
> Assuming you want to add support for a new filesystem in ompio, first
> step is to implement a new component in the fs framework the framework
> is in /ompi/mca/fs, and each component is in its own directory (for
> example ompi/mca/fs/gpfs)
>
> There are a some configury tricks (create a configure.m4, add Makefile
> to autoconf, ...) to make sure your component is even compiled.
> If you are struggling with these, feel free to open a Pull Request to
> get some help fixing the missing bits.
>
> Cheers,
>
> Gilles
>
> On Sun, Nov 1, 2020 at 12:18 PM Ognen Duzlevski via users
> wrote:
>>
>> Hello!
>>
>> If I wanted to support a specific filesystem in open mpi, how is this
>> done? What code in the source tree does it?
>>
>> Thanks!
>> Ognen
Re: [OMPI users] ompe support for filesystems
Edgar,
Thanks - this is exactly what I was looking for. I started going through
the code in earnest and trying to figure out exactly where the magic
happens. I may have more questions :-)
Ognen
Gabriel, Edgar via users writes:
> the ompio software infrastructure has multiple frameworks.
>
> fs framework: abstracts out file system level operations (open, close, etc)
>
> fbtl framework: provides the abstractions and implementations of *individual*
> file I/O operations (seek,read,write, iread,iwrite)
>
> fcoll framework: provides the abstractions and implementations of
> *collective* file I/O operations ( read_all, write_all, etc.)
>
> sharedfp framework: provides the abstractions and implementations *shared
> file pointer* file I/O operations (read_shared, write_shared, read_ordered,
> write_ordered).
>
> Feel free to ping me also directly if you need more assistance. If you are
> looking for a reference and more explanations, please have a look at the
> following paper:
>
> Mohamad Chaarawi, Edgar Gabriel, Rainer Keller, Richard Graham, George
> Bosilca and Jack Dongarra, 'OMPIO: A Modular Software Architecture for MPI
> I/O', in Y. Cotronis, A. Danalis, D. Nikolopoulos, J. Dongarra, (Eds.)
> 'Recent Advances in Message Passing Interface', LNCS vol. 6960, pp. 81-89,
> Springer, 2011.
>
> http://www2.cs.uh.edu/~gabriel/publications/EuroMPI11_OMPIO.pdf
>
> Best regards
> Edgar
>
> -Original Message-
> From: users On Behalf Of Ognen Duzlevski
> via users
> Sent: Monday, November 2, 2020 7:54 AM
> To: Open MPI Users
> Cc: Ognen Duzlevski
> Subject: Re: [OMPI users] ompe support for filesystems
>
> Gilles,
>
> Thank you for replying.
>
> I took a look at the code and am curious to understand where the actual
> read/write/seek etc. operations are implemented. From what I can
> see/understand - what you pointed me to implements file open/close etc.
> operations that pertain to particular filesystems.
>
> I then tried to figure out the read/write/seek etc. operations and can see
> that a MPI_File structure appears to have a f_io_selected_module member,
> whose v_2_0_0 member seems to have the list of pointers to all the
> functionals dealing with the actual file write/read/seek functionality. Is
> this correct?
>
> What I would like to figure out is where the actual writes or reads happen
> (as in the underlying filesystem's implementations). I imagine for some
> filesystems a write, for example, is not just a simple call to the write onto
> disk but involves a bit more logic/magic.
>
> Thanks!
> Ognen
>
>
> Gilles Gouaillardet via users writes:
>
>> Hi Ognen,
>>
>> MPI-IO is implemented by two components:
>> - ROMIO (from MPICH)
>> - ompio ("native" Open MPI MPI-IO, default component unless running
>> on Lustre)
>>
>> Assuming you want to add support for a new filesystem in ompio, first
>> step is to implement a new component in the fs framework the framework
>> is in /ompi/mca/fs, and each component is in its own directory (for
>> example ompi/mca/fs/gpfs)
>>
>> There are a some configury tricks (create a configure.m4, add Makefile
>> to autoconf, ...) to make sure your component is even compiled.
>> If you are struggling with these, feel free to open a Pull Request to
>> get some help fixing the missing bits.
>>
>> Cheers,
>>
>> Gilles
>>
>> On Sun, Nov 1, 2020 at 12:18 PM Ognen Duzlevski via users
>> wrote:
>>>
>>> Hello!
>>>
>>> If I wanted to support a specific filesystem in open mpi, how is this
>>> done? What code in the source tree does it?
>>>
>>> Thanks!
>>> Ognen
