RDMA: Increasing RPCRDMA_MAX_DATA_SEGS
Steve Dickson [Thu, 21 Jul 2011 17:49:02 +0000 (13:49 -0400)]
Our performance team has noticed that increasing
RPCRDMA_MAX_DATA_SEGS from 8 to 64 significantly
increases throughput when using the RDMA transport.

Signed-off-by: Steve Dickson <steved@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

net/sunrpc/xprtrdma/xprt_rdma.h

index cae761a..5d1cfe5 100644 (file)
@@ -109,7 +109,7 @@ struct rpcrdma_ep {
  */
 
 /* temporary static scatter/gather max */
-#define RPCRDMA_MAX_DATA_SEGS  (8)     /* max scatter/gather */
+#define RPCRDMA_MAX_DATA_SEGS  (64)    /* max scatter/gather */
 #define RPCRDMA_MAX_SEGS       (RPCRDMA_MAX_DATA_SEGS + 2) /* head+tail = 2 */
 #define MAX_RPCRDMAHDR (\
        /* max supported RPC/RDMA header */ \