Using 8K as a minimal CQ length

- For now we'll use 8192 as a base value
 - We leave the adjust_cq() as is
 - For the long term we can work on an appropriate setting to expose through the INI file.

8K CQEs are 512K per process, which is 8MB for ppn=16

This commit was SVN r26877.

ompi/mca/btl/openib/btl_openib_mca.c

@@ -253,7 +253,7 @@ int btl_openib_register_mca_params(void)
                   "(CQs are automatically sized based on the number "
                   "of peer MPI processes; this value determines the "
                   "*minimum* size of all CQs)",
-                  1500, &ival, REGINT_GE_ONE));
+                  8192, &ival, REGINT_GE_ONE));
     mca_btl_openib_component.ib_cq_size[BTL_OPENIB_LP_CQ] =
         mca_btl_openib_component.ib_cq_size[BTL_OPENIB_HP_CQ] = (uint32_t) ival;