[openib-general] RE: [PATCH] Opensm - add info in vendor error printing

[Yael Kalka]

Hello all,

During some opensm tests we've encountered a situation where a call
to umad_send() fails on very large mads (on mads of size ~90,000).
Is there some limitation on the size of the mads that can be sent?

Reproduction of the issue is simple:
Run opensm
Then run osmtest -f m -M 3
What the osmtest does in this case is try to create as many multicast
groups as possible (for all the possible MC_lids), and then
does an SA query on all the multicast groups that exist.
OpenSM will then try to answer with a huge group of multicast records,
and when opensm does umad_send() - it fails.

Any ideas why this happens?

Thanks,
Yael