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Subject: Re: [OMPI devel] IBCM error
From: Sean Hefty (sean.hefty_at_[hidden])
Date: 2008-07-14 17:48:25


>Ah! I did not realize that there were other services on the machine
>that were using / reserving IBCM service ID's.

Intel MPI hit a similar problem a long, long time ago.

>Is there a service ID range that is guaranteed to be available for
>user apps?

I need to check on this. You may want to look at section A3.2.3 of the spec.
If you set the first byte (network order) to 0x00, and the 2nd byte to 0x01,
then you hit a 'reserved' range that probably isn't being used currently.

If you don't care what the service ID is, you can specify 0, and the kernel will
assign one. The assigned value can be retrieved by calling ib_cm_attr_id().
(I'm assuming that you communicate the IDs out of band somehow.)

- Sean