Date: Fri, 20 Jul 2018 12:38:08 +0000 (UTC) From: Rick Macklem <rmacklem@FreeBSD.org> To: src-committers@freebsd.org, svn-src-projects@freebsd.org Subject: svn commit: r336544 - projects/pnfs-planb-server/sys/fs/nfs Message-ID: <201807201238.w6KCc8Pl045854@repo.freebsd.org>
next in thread | raw e-mail | index | archive | help
Author: rmacklem Date: Fri Jul 20 12:38:07 2018 New Revision: 336544 URL: https://svnweb.freebsd.org/changeset/base/336544 Log: Update the comments and add a sysctl to set the retry limit for connections from clients to DSs. This is for the client side pNFS and head/current will be getting this commit soon. Modified: projects/pnfs-planb-server/sys/fs/nfs/nfs_commonkrpc.c Modified: projects/pnfs-planb-server/sys/fs/nfs/nfs_commonkrpc.c ============================================================================== --- projects/pnfs-planb-server/sys/fs/nfs/nfs_commonkrpc.c Fri Jul 20 12:32:17 2018 (r336543) +++ projects/pnfs-planb-server/sys/fs/nfs/nfs_commonkrpc.c Fri Jul 20 12:38:07 2018 (r336544) @@ -106,6 +106,7 @@ static int nfs_bufpackets = 4; static int nfs_reconnects; static int nfs3_jukebox_delay = 10; static int nfs_skip_wcc_data_onerr = 1; +static int nfs_dsretries = 2; SYSCTL_DECL(_vfs_nfs); @@ -117,6 +118,8 @@ SYSCTL_INT(_vfs_nfs, OID_AUTO, nfs3_jukebox_delay, CTL "Number of seconds to delay a retry after receiving EJUKEBOX"); SYSCTL_INT(_vfs_nfs, OID_AUTO, skip_wcc_data_onerr, CTLFLAG_RW, &nfs_skip_wcc_data_onerr, 0, "Disable weak cache consistency checking when server returns an error"); +SYSCTL_INT(_vfs_nfs, OID_AUTO, dsretries, CTLFLAG_RW, &nfs_dsretries, 0, + "Number of retries for a DS RPC before failure"); static void nfs_down(struct nfsmount *, struct thread *, const char *, int, int); @@ -303,14 +306,20 @@ newnfs_connect(struct nfsmount *nmp, struct nfssockreq if (cred != NULL) { if (NFSHASSOFT(nmp)) { /* - * This should be a DS mount. If the - * timeout is set to 1/4th of the lease - * duration, the DS should be disabled - * at approximately 1/2 lease duration, - * due to a retry count of 2. - * This will hopefully cause the client - * to continue without the disabled - * DS in less than the lease duration. + * This should be a DS mount. + * Use CLSET_TIMEOUT to set the timeout + * for connections to DSs instead of + * specifying a timeout on each RPC. + * This is done so that SO_SNDTIMEO + * is set on the TCP socket as well + * as specifying a time limit when + * waiting for an RPC reply. Useful + * if the send queue for the TCP + * connection has become constipated, + * due to a failed DS. + * The choice of lease_duration / 4 is + * fairly arbitrary, but seems to work + * ok, with a lower bound of 10sec. */ timo.tv_sec = nfsrv_lease / 4; if (timo.tv_sec < 10) @@ -346,6 +355,10 @@ newnfs_connect(struct nfsmount *nmp, struct nfssockreq * not maintain open/lock state and is the * only case where using a "soft" mount is * recommended for NFSv4. + * For mounts from the MDS to DS, this is done + * via mount options, but that is not the case + * here. The retry limit here can be adjusted + * via the sysctl vfs.nfs.dsretries. * See the comment above w.r.t. timeout. */ timo.tv_sec = nfsrv_lease / 4; @@ -353,7 +366,7 @@ newnfs_connect(struct nfsmount *nmp, struct nfssockreq timo.tv_sec = 10; timo.tv_usec = 0; CLNT_CONTROL(client, CLSET_TIMEOUT, &timo); - retries = 2; + retries = nfs_dsretries; } } } else {
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?201807201238.w6KCc8Pl045854>