[ewg] RE: OFED libraries - on the web at last

[Todd Rimmer]

> From: Sasha Khapyorsky [mailto:sashakvolt at gmail.com] On Behalf Of Sasha
> Khapyorsky
> Sent: Wednesday, June 17, 2009 11:32 AM
> To: Todd Rimmer
> Cc: Tziporet Koren; ewg at lists.openfabrics.org
> Subject: Re: [ewg] RE: OFED libraries - on the web at last
> 
> On 08:14 Wed 17 Jun     , Todd Rimmer wrote:
> >
> > The issue isn't with the management tree.  It's with the mvapich
> included in OFED 1.4.1 and previous versions.
> 
> Then it should be fixed.
[Todd Rimmer] Agreed, but customers will need a few releases of notice that they should recompile their apps.

> 
> > It links with libibcommon and as a result,
> 
> Do you know why exactly was it linked (and how)? I searched over
> mvapich
> source and didn't find any references in sources and makefiles. It is
> only mentioned in spec files. So is there any issue really?
[Todd Rimmer] Yes, the .spec file controls what libraries mvapich uses, that same list of libraries is then part of mpicc and mpif77 and used to link all applications built with mvapich.

> 
> > ALL end user and ISV apps linked with mvapich also link with
> libibcommon.
> >
> > This means that in moving to OFED 1.5 end users and ISVs would have
> to recompile all their apps.  Such a change should not be taken
> lightly.  Instead we should provide what is needed in OFED 1.5 such
> that existing app binaries will continue to work (might be as simple as
> stubbed library).  Then we can issue notice to end users and ISVs that
> their apps will need to be rebuilt and allow them at least 1 release to
> accomplish that.
> >
> 
> AFAIR libibcommon removal was discussed on the list couple of times
> before, during and after OFED-1.4.
[Todd Rimmer] Yes, but unfortunately it didn't come into practice in mvapich in OFED 1.4.1 or previous.

ABI compatibility is an important requirement.  In this case the ABI is that of applications built with mvapich.  Is it ideal, NO.  But we can't penalize customers.  I suspect a dummy library would satisfy the mvapich need, but that would need to be confirmed (FYI, OFED 1.4.1 libibumad also references ibcommon).

> 
> Sasha