Open MPI logo

Open MPI Development Mailing List Archives

  |   Home   |   Support   |   FAQ   |   all Development mailing list

Subject: Re: [OMPI devel] Fwd: [Open MPI] #1927: v1.3 COMM_SPAWN loop test fails after ~120 spawns
From: Ralph Castain (rhc_at_[hidden])
Date: 2009-06-09 07:46:05


I don't think it would be very hard - I would have to create a patch
for it, but the fix is completely contained in one file and location.

I would like to have someone else test it, though, before we move it
across. It worked for me, but since it is a race condition, that isn't
entirely convincing.

On Jun 9, 2009, at 5:41 AM, Jeff Squyres wrote:

> I'd be in favor of bringing this to v1.3. Are there other
> dependencies / would it be difficult?
>
>
> Begin forwarded message:
>
>> From: "Open MPI" <bugs_at_[hidden]>
>> Date: June 8, 2009 11:31:20 AM PDT
>> Cc: <bugs_at_[hidden]>
>> Subject: Re: [Open MPI] #1927: v1.3 COMM_SPAWN loop test fails
>> after ~120 spawns
>>
>> #1927: v1.3 COMM_SPAWN loop test fails after ~120 spawns
>> -----------------------
>> +----------------------------------------------------
>> Reporter: jsquyres | Owner: rhc
>> Type: defect | Status: closed
>> Priority: critical | Milestone: Open MPI 1.3.4
>> Version: 1.3 branch | Resolution: fixed
>> Keywords: |
>> -----------------------
>> +----------------------------------------------------
>> Changes (by rhc):
>>
>> * status: new => closed
>> * resolution: => fixed
>>
>>
>> Comment:
>>
>> This was due to a very tight loop on comm_spawn not giving enough
>> time for
>> the prior proc to completely terminate (and thus free its file
>> descriptors) before the next proc was launched. Eventually, we
>> built up a
>> backlog of terminations to process and ran out of fd's.
>>
>> We introduced a check-and-delay in the code that detects we don't
>> have
>> enough fd's to launch another proc, and then waits a second to see if
>> enough become free before aborting.
>>
>> Fixed in trunk - can see if we want to bring it to 1.3.
>>
>> --
>> Ticket URL: <https://svn.open-mpi.org/trac/ompi/ticket/1927#comment:
>> 3>
>> Open MPI <http://www.open-mpi.org/>
>>
>>
>
>
> --
> Jeff Squyres
> Cisco Systems
>
> _______________________________________________
> devel mailing list
> devel_at_[hidden]
> http://www.open-mpi.org/mailman/listinfo.cgi/devel