commit cd8db6f4c0c49ab5f954014d72b233dd9e73fc78 Author: Chuck Lever Date: Thu Aug 11 16:25:14 2005 -0400 [PATCH] NFS: use a constant value for TCP retransmit timeouts Implement a best practice: don't use exponential backoff when computing retransmit timeout values on TCP connections, but simply retransmit at regular intervals. This also fixes a bug introduced when xprt_reset_majortimeo() was added. Test-plan: Enable RPC debugging and watch timeout behavior on a NFS/TCP mount. Version: Thu, 11 Aug 2005 16:02:19 -0400 Signed-off-by: Chuck Lever Signed-off-by: Trond Myklebust --- fs/nfs/inode.c | 73 +++++++++++++++++++++++++----------------------------- net/sunrpc/xprt.c | 4 +- 2 files changed, 37 insertions(+), 40 deletions(-) Index: linux-2.6.13-rc6/fs/nfs/inode.c =================================================================== --- linux-2.6.13-rc6.orig/fs/nfs/inode.c +++ linux-2.6.13-rc6/fs/nfs/inode.c @@ -356,6 +356,35 @@ out_no_root: return no_root_error; } +static void nfs_init_timeout_values(struct rpc_timeout *to, int proto, unsigned int timeo, unsigned int retrans) +{ + to->to_initval = timeo * HZ / 10; + to->to_retries = retrans; + if (!to->to_retries) + to->to_retries = 2; + + switch (proto) { + case IPPROTO_TCP: + if (!to->to_initval) + to->to_initval = 60 * HZ; + if (to->to_initval > RPC_MAX_TCP_TIMEOUT) + to->to_initval = RPC_MAX_TCP_TIMEOUT; + to->to_increment = to->to_initval; + to->to_maxval = to->to_initval + (to->to_increment * to->to_retries); + to->to_exponential = 0; + break; + case IPPROTO_UDP: + default: + if (!to->to_initval) + to->to_initval = 11 * HZ / 10; + if (to->to_initval > RPC_MAX_UDP_TIMEOUT) + to->to_initval = RPC_MAX_UDP_TIMEOUT; + to->to_maxval = RPC_MAX_UDP_TIMEOUT; + to->to_exponential = 1; + break; + } +} + /* * Create an RPC client handle. */ @@ -365,22 +394,12 @@ nfs_create_client(struct nfs_server *ser struct rpc_timeout timeparms; struct rpc_xprt *xprt = NULL; struct rpc_clnt *clnt = NULL; - int tcp = (data->flags & NFS_MOUNT_TCP); + int proto = (data->flags & NFS_MOUNT_TCP) ? IPPROTO_TCP : IPPROTO_UDP; - /* Initialize timeout values */ - timeparms.to_initval = data->timeo * HZ / 10; - timeparms.to_retries = data->retrans; - timeparms.to_maxval = tcp ? RPC_MAX_TCP_TIMEOUT : RPC_MAX_UDP_TIMEOUT; - timeparms.to_exponential = 1; - - if (!timeparms.to_initval) - timeparms.to_initval = (tcp ? 600 : 11) * HZ / 10; - if (!timeparms.to_retries) - timeparms.to_retries = 5; + nfs_init_timeout_values(&timeparms, proto, data->timeo, data->retrans); /* create transport and client */ - xprt = xprt_create_proto(tcp ? IPPROTO_TCP : IPPROTO_UDP, - &server->addr, &timeparms); + xprt = xprt_create_proto(proto, &server->addr, &timeparms); if (IS_ERR(xprt)) { dprintk("%s: cannot create RPC transport. Error = %ld\n", __FUNCTION__, PTR_ERR(xprt)); @@ -1672,7 +1691,7 @@ static int nfs4_fill_super(struct super_ struct rpc_clnt *clnt = NULL; struct rpc_timeout timeparms; rpc_authflavor_t authflavour; - int proto, err = -EIO; + int err = -EIO; sb->s_blocksize_bits = 0; sb->s_blocksize = 0; @@ -1690,30 +1709,8 @@ static int nfs4_fill_super(struct super_ server->acdirmax = data->acdirmax*HZ; server->rpc_ops = &nfs_v4_clientops; - /* Initialize timeout values */ - - timeparms.to_initval = data->timeo * HZ / 10; - timeparms.to_retries = data->retrans; - timeparms.to_exponential = 1; - if (!timeparms.to_retries) - timeparms.to_retries = 5; - proto = data->proto; - /* Which IP protocol do we use? */ - switch (proto) { - case IPPROTO_TCP: - timeparms.to_maxval = RPC_MAX_TCP_TIMEOUT; - if (!timeparms.to_initval) - timeparms.to_initval = 600 * HZ / 10; - break; - case IPPROTO_UDP: - timeparms.to_maxval = RPC_MAX_UDP_TIMEOUT; - if (!timeparms.to_initval) - timeparms.to_initval = 11 * HZ / 10; - break; - default: - return -EINVAL; - } + nfs_init_timeout_values(&timeparms, data->proto, data->timeo, data->retrans); clp = nfs4_get_client(&server->addr.sin_addr); if (!clp) { @@ -1738,7 +1735,7 @@ static int nfs4_fill_super(struct super_ down_write(&clp->cl_sem); if (IS_ERR(clp->cl_rpcclient)) { - xprt = xprt_create_proto(proto, &server->addr, &timeparms); + xprt = xprt_create_proto(data->proto, &server->addr, &timeparms); if (IS_ERR(xprt)) { up_write(&clp->cl_sem); err = PTR_ERR(xprt); Index: linux-2.6.13-rc6/net/sunrpc/xprt.c =================================================================== --- linux-2.6.13-rc6.orig/net/sunrpc/xprt.c +++ linux-2.6.13-rc6/net/sunrpc/xprt.c @@ -1453,7 +1453,7 @@ xprt_default_timeout(struct rpc_timeout if (proto == IPPROTO_UDP) xprt_set_timeout(to, 5, 5 * HZ); else - xprt_set_timeout(to, 5, 60 * HZ); + xprt_set_timeout(to, 2, 60 * HZ); } /* @@ -1464,7 +1464,7 @@ xprt_set_timeout(struct rpc_timeout *to, { to->to_initval = to->to_increment = incr; - to->to_maxval = incr * retr; + to->to_maxval = to->to_initval + (incr * retr); to->to_retries = retr; to->to_exponential = 0; }