From: Chuck Lever Subject: [PATCH] new timeout behavior for RPC requests on TCP sockets Date: Tue, 12 Nov 2002 18:15:48 -0500 (EST) Sender: nfs-admin@lists.sourceforge.net Message-ID: Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Cc: Linux NFS List , Linux Kernel Mailing List Return-path: Received: from spacewalker.citi.umich.edu ([141.211.133.39]) by usw-sf-list1.sourceforge.net with esmtp (Exim 3.31-VA-mm2 #1 (Debian)) id 18BkGC-0001Tg-00 for ; Tue, 12 Nov 2002 15:15:57 -0800 To: Linus Torvalds Errors-To: nfs-admin@lists.sourceforge.net List-Help: List-Post: List-Subscribe: , List-Id: Discussion of NFS under Linux development, interoperability, and testing. List-Unsubscribe: , List-Archive: make RPC timeout behavior over TCP sockets behave more like reference client implementations. reference behavior is to transmit the same request three times at 60 second intervals; if there is no response, close and reestablish the socket connection. we modify the Linux RPC client as follows: + after a minor retransmit timeout, use the same timeout value when retrying on a TCP socket rather than doubling the value + after a major retransmit timeout, close the socket and attempt to reestablish a fresh TCP connection note that today mount uses a 6 second timeout with 5 retries for NFS over TCP by default; proper default behavior is 2 retries each with 60 second timeouts. a separate patch for mount is pending. against 2.5.47. diff -ruN 10-connect3/include/linux/sunrpc/xprt.h 11-timeout/include/linux/sunrpc/xprt.h --- 10-connect3/include/linux/sunrpc/xprt.h Tue Nov 12 16:18:57 2002 +++ 11-timeout/include/linux/sunrpc/xprt.h Tue Nov 12 17:06:16 2002 @@ -182,9 +182,10 @@ void xprt_reserve(struct rpc_task *); void xprt_transmit(struct rpc_task *); void xprt_receive(struct rpc_task *); -int xprt_adjust_timeout(struct rpc_timeout *); +void xprt_adjust_timeout(struct rpc_timeout *); void xprt_release(struct rpc_task *); void xprt_connect(struct rpc_task *); +void xprt_disconnect(struct rpc_xprt *); int xprt_clear_backlog(struct rpc_xprt *); void xprt_sock_setbufsize(struct rpc_xprt *); diff -ruN 10-connect3/net/sunrpc/clnt.c 11-timeout/net/sunrpc/clnt.c --- 10-connect3/net/sunrpc/clnt.c Tue Nov 12 16:19:25 2002 +++ 11-timeout/net/sunrpc/clnt.c Tue Nov 12 17:13:24 2002 @@ -667,6 +667,9 @@ if (clnt->cl_autobind) clnt->cl_port = 0; task->tk_action = call_bind; + /* A disconnect can happen after only part of an RPC was + * sent on a TCP socket. send all of this request again */ + req->rq_bytes_sent = 0; break; case -EAGAIN: task->tk_action = call_transmit; @@ -688,20 +691,34 @@ * 6a. Handle RPC timeout * We do not release the request slot, so we keep using the * same XID for all retransmits. + * For stream transports, shut down the transport socket when + * a request sees a major time out. When any request on this + * connection is retried, the FSM notices the socket has been + * shut down, and attempts to reconnect. */ static void call_timeout(struct rpc_task *task) { struct rpc_clnt *clnt = task->tk_client; - struct rpc_timeout *to = &task->tk_rqstp->rq_timeout; + struct rpc_xprt *xprt = clnt->cl_xprt; + struct rpc_rqst *req = task->tk_rqstp; + struct rpc_timeout *to = &req->rq_timeout; - if (xprt_adjust_timeout(to)) { - dprintk("RPC: %4d call_timeout (minor)\n", task->tk_pid); + if (!xprt->stream) + xprt_adjust_timeout(to); + + if (to->to_retries--) { + dprintk("RPC: %4d call_timeout (minor, retries=%d)\n", + task->tk_pid, to->to_retries); goto retry; } - to->to_retries = clnt->cl_timeout.to_retries; + to->to_retries = xprt->timeout.to_retries; dprintk("RPC: %4d call_timeout (major)\n", task->tk_pid); + + if (xprt->stream) + xprt_disconnect(xprt); + if (clnt->cl_softrtry) { if (clnt->cl_chatty && !task->tk_exit) printk(KERN_NOTICE "%s: server %s not responding, timed out\n", @@ -710,15 +727,18 @@ return; } - if (clnt->cl_chatty && !(task->tk_flags & RPC_CALL_MAJORSEEN) && rpc_ntimeo(&clnt->cl_rtt) > 7) { - task->tk_flags |= RPC_CALL_MAJORSEEN; - printk(KERN_NOTICE "%s: server %s not responding, still trying\n", - clnt->cl_protname, clnt->cl_server); + if (clnt->cl_chatty && !(task->tk_flags & RPC_CALL_MAJORSEEN)) { + if (xprt->stream || (rpc_ntimeo(&clnt->cl_rtt) > 7)) { + task->tk_flags |= RPC_CALL_MAJORSEEN; + printk(KERN_NOTICE "%s: server %s not responding, still trying\n", + clnt->cl_protname, clnt->cl_server); + } } if (clnt->cl_autobind) clnt->cl_port = 0; retry: + req->rq_bytes_sent = 0; /* send all of this request again */ clnt->cl_stats->rpcretrans++; task->tk_action = call_bind; task->tk_status = 0; diff -ruN 10-connect3/net/sunrpc/xprt.c 11-timeout/net/sunrpc/xprt.c --- 10-connect3/net/sunrpc/xprt.c Tue Nov 12 16:31:08 2002 +++ 11-timeout/net/sunrpc/xprt.c Tue Nov 12 17:06:16 2002 @@ -85,7 +85,6 @@ static void xprt_request_init(struct rpc_task *, struct rpc_xprt *); static void do_xprt_transmit(struct rpc_task *); static inline void do_xprt_reserve(struct rpc_task *); -static void xprt_disconnect(struct rpc_xprt *); static void xprt_conn_status(struct rpc_task *task); static struct rpc_xprt * xprt_setup(int proto, struct sockaddr_in *ap, struct rpc_timeout *to); @@ -336,7 +335,7 @@ /* * Adjust timeout values etc for next retransmit */ -int +void xprt_adjust_timeout(struct rpc_timeout *to) { if (to->to_retries > 0) { @@ -362,7 +361,7 @@ } pprintk("RPC: %lu %s\n", jiffies, to->to_retries? "retrans" : "timeout"); - return to->to_retries-- > 0; + return; } /* @@ -394,7 +393,7 @@ /* * Mark a transport as disconnected */ -static void +void xprt_disconnect(struct rpc_xprt *xprt) { dprintk("RPC: disconnected transport %p\n", xprt); ------------------------------------------------------- This sf.net email is sponsored by: To learn the basics of securing your web site with SSL, click here to get a FREE TRIAL of a Thawte Server Certificate: http://www.gothawte.com/rd522.html _______________________________________________ NFS maillist - NFS@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/nfs