inserted in the ompi_proc_list as soon as it is created and it
is removed only upon the call to the destructor. In ompi_proc_finalize
we loop over all procs in ompi_proc_finalize and release them once.
However, as a proc is not removed from this list right away, we
decrease the ref count for each proc until it reach zero and the
proc is finally removed. Thus, we cannot clean the BML/BTL after
the call the ompi_proc_finalize.
A quick fix is to delay the call to ompi_proc_finalize until all
other frameworks have been finalized, and then the behavior
depicted above will give the expected outcome.
Background: In order to support atomics each btl needs to provide support
for communicating with self unless the btl module can guarantee global
atomicity. Before this commit bml/r2 discarded any BTL with lower
exclusivity than an existing send btl. This would cause the BML to
discard any btl other than self.
The new behavior is as follows:
- If an exisiting send btl has higher exclusivity then the btl will not be
added to the send btl list for the endpoint.
- If a btl provides RDMA support then it is always added to the rdma btl
list.
- bml_btl weight for send btls is now calculated across all send btls.
- bml_btl weight for rdma btls is now calculated across all rdma btls.
With this change self should still win as the only send btl for loopback
without disqualifying other btls (ugni, openib) for atomic operations.
attempting to break the get into multiple rdma fragments
A little background. Historically ob1 always registered the entire memory
region when the RGET protocol was in use. This changed when Mellanox
added support to fragment RGET using the btl_prepare_dst function. Now
that the BTL layer has changed to split out the limits of get/put there
is explicit fragmentation code in ob1. Before this commit the registration
was still done per RGET fragment.
This commit will attempt to register the entire region before creating
RGET fragments. If the registration is successfull then all RGET
fragments will use this registration otherwise they will each attempt
to register their own segment of the receive buffer. If that fails
enough times each fragment will give up and fall back on send/recv.
PSM has issues when trying calling psm_ep_connect() more than once for a
specific peer. Use the psm_ep_connect mask argument to avoid connecting
to processes that are already connected.
OMPI ticket #268.