From c209e49ceac0ff479f79ac5cd2fbf8be80621203 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Wed, 24 Apr 2019 09:39:59 -0400 Subject: xprtrdma: More Send completion batching Instead of using a fixed number, allow the amount of Send completion batching to vary based on the client's maximum credit limit. - A larger default gives a small boost to IOPS throughput - Reducing it based on max_requests gives a safe result when the max credit limit is cranked down (eg. when the device has a small max_qp_wr). Signed-off-by: Chuck Lever Signed-off-by: Anna Schumaker --- net/sunrpc/xprtrdma/verbs.c | 4 +--- net/sunrpc/xprtrdma/xprt_rdma.h | 10 ---------- 2 files changed, 1 insertion(+), 13 deletions(-) diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c index 1ad25190f2d1..1ed761a12f86 100644 --- a/net/sunrpc/xprtrdma/verbs.c +++ b/net/sunrpc/xprtrdma/verbs.c @@ -521,9 +521,7 @@ rpcrdma_ep_create(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia, ep->rep_attr.cap.max_send_sge, ep->rep_attr.cap.max_recv_sge); - /* set trigger for requesting send completion */ - ep->rep_send_batch = min_t(unsigned int, RPCRDMA_MAX_SEND_BATCH, - cdata->max_requests >> 2); + ep->rep_send_batch = cdata->max_requests >> 3; ep->rep_send_count = ep->rep_send_batch; init_waitqueue_head(&ep->rep_connect_wait); ep->rep_receive_count = 0; diff --git a/net/sunrpc/xprtrdma/xprt_rdma.h b/net/sunrpc/xprtrdma/xprt_rdma.h index 8afb5fc1de05..f8563937c8c6 100644 --- a/net/sunrpc/xprtrdma/xprt_rdma.h +++ b/net/sunrpc/xprtrdma/xprt_rdma.h @@ -232,16 +232,6 @@ struct rpcrdma_sendctx { struct ib_sge sc_sges[]; }; -/* Limit the number of SGEs that can be unmapped during one - * Send completion. This caps the amount of work a single - * completion can do before returning to the provider. - * - * Setting this to zero disables Send completion batching. - */ -enum { - RPCRDMA_MAX_SEND_BATCH = 7, -}; - /* * struct rpcrdma_mr - external memory region metadata * -- cgit