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From: Gleb Natapov (glebn_at_[hidden])
Date: 2006-02-07 10:24:16


Hello Galen,

 I have a question about {min,max}_{send,rdma}_size btl parameters.
Can you explain to me what is the meaning of each of them. I thought I
understand but it seams I was wrong :).

I thought that one RDMA transfer cannot be bigger then max_rdma_size and
if application tries to send buffer bigger than that the transaction
will be split to several RDMA operation. But my test shows this is not
the case.

By the way I think the following should be applied:

Index: btl_openib_component.c
===================================================================
--- btl_openib_component.c (revision 8901)
+++ btl_openib_component.c (working copy)
@@ -195,7 +195,7 @@
                                       1024*1024, (int*) &mca_btl_openib_module.super.btl_min_rdma_size);
     mca_btl_openib_param_register_int("max_rdma_size", "maximium rdma size",
                                       1024*1024, (int*) &mca_btl_openib_module.super.btl_max_rdma_size);
- mca_btl_openib_param_register_int("flags", "BTL flags, SEND=0, PUT=1, GET=2",
+ mca_btl_openib_param_register_int("flags", "BTL flags, SEND=1, PUT=2, GET=4",
                                       MCA_BTL_FLAGS_PUT, (int*) &mca_btl_openib_module.super.btl_flags);
     
     mca_btl_openib_param_register_int("bandwidth", "Approximate maximum bandwidth of interconnect",

--
			Gleb.