Branch b1_x_lnet_gate

Allow user to specify small value for o2iblnd::concurrent_sends

b=15983
i=isaac

diff --git a/lnet/klnds/o2iblnd/o2iblnd_modparams.c b/lnet/klnds/o2iblnd/o2iblnd_modparams.c
index 10edb5d..91c7520 100644 (file)
--- a/lnet/klnds/o2iblnd/o2iblnd_modparams.c
+++ b/lnet/klnds/o2iblnd/o2iblnd_modparams.c
@@ -316,8 +316,14 @@ kiblnd_tunables_init (void)
 
         if (*kiblnd_tunables.kib_concurrent_sends > IBLND_RX_MSGS)
                 *kiblnd_tunables.kib_concurrent_sends = IBLND_RX_MSGS;
-        if (*kiblnd_tunables.kib_concurrent_sends < IBLND_MSG_QUEUE_SIZE)
-                *kiblnd_tunables.kib_concurrent_sends = IBLND_MSG_QUEUE_SIZE;
+        if (*kiblnd_tunables.kib_concurrent_sends < IBLND_MSG_QUEUE_SIZE / 2)
+                *kiblnd_tunables.kib_concurrent_sends = IBLND_MSG_QUEUE_SIZE / 2;
+
+        if (*kiblnd_tunables.kib_concurrent_sends < IBLND_MSG_QUEUE_SIZE) {
+                CWARN("Concurrent sends %d is lower than message queue size: %d, "
+                      "performance may drop slightly.\n",
+                      *kiblnd_tunables.kib_concurrent_sends, IBLND_MSG_QUEUE_SIZE);
+        }
 
         return 0;
 }