From d9ef5a8c26aab09762afce43df64736720b4860e Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Mon, 20 Mar 2006 13:44:13 -0500 Subject: NFS: introduce mechanism for tracking NFS client metrics Add a per-superblock performance counter facility to the NFS client. This facility mimics the counters available for block devices and for networking. Expose these new counters via the new /proc/self/mountstats interface. Thanks to Andrew Morton and Trond Myklebust for their review and comments. Test plan: fsx and iozone on UP and SMP systems, with and without pre-emption. Watch for memory overwrite bugs, and performance loss (significantly more CPU required per op). Signed-off-by: Chuck Lever Signed-off-by: Trond Myklebust --- fs/nfs/inode.c | 103 +++++++++++++++++++++++++++++-- fs/nfs/iostat.h | 152 ++++++++++++++++++++++++++++++++++++++++++++++ include/linux/nfs_fs_sb.h | 3 + 3 files changed, 252 insertions(+), 6 deletions(-) create mode 100644 fs/nfs/iostat.h diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c index 827d69255b1ba5..86b756f44e2714 100644 --- a/fs/nfs/inode.c +++ b/fs/nfs/inode.c @@ -42,6 +42,7 @@ #include "nfs4_fs.h" #include "callback.h" #include "delegation.h" +#include "iostat.h" #define NFSDBG_FACILITY NFSDBG_VFS #define NFS_PARANOIA 1 @@ -65,6 +66,7 @@ static void nfs_clear_inode(struct inode *); static void nfs_umount_begin(struct super_block *); static int nfs_statfs(struct super_block *, struct kstatfs *); static int nfs_show_options(struct seq_file *, struct vfsmount *); +static int nfs_show_stats(struct seq_file *, struct vfsmount *); static void nfs_zap_acl_cache(struct inode *); static struct rpc_program nfs_program; @@ -78,6 +80,7 @@ static struct super_operations nfs_sops = { .clear_inode = nfs_clear_inode, .umount_begin = nfs_umount_begin, .show_options = nfs_show_options, + .show_stats = nfs_show_stats, }; /* @@ -290,6 +293,12 @@ nfs_sb_init(struct super_block *sb, rpc_authflavor_t authflavor) } sb->s_root->d_op = server->rpc_ops->dentry_ops; + server->io_stats = nfs_alloc_iostats(); + if (!server->io_stats) { + no_root_error = -ENOMEM; + goto out_no_root; + } + /* Get some general file system info */ if (server->namelen == 0 && server->rpc_ops->pathconf(server, &server->fh, &pathinfo) >= 0) @@ -582,7 +591,7 @@ nfs_statfs(struct super_block *sb, struct kstatfs *buf) } -static int nfs_show_options(struct seq_file *m, struct vfsmount *mnt) +static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss, int showdefaults) { static struct proc_nfs_info { int flag; @@ -598,20 +607,19 @@ static int nfs_show_options(struct seq_file *m, struct vfsmount *mnt) { 0, NULL, NULL } }; struct proc_nfs_info *nfs_infop; - struct nfs_server *nfss = NFS_SB(mnt->mnt_sb); char buf[12]; char *proto; seq_printf(m, ",vers=%d", nfss->rpc_ops->version); seq_printf(m, ",rsize=%d", nfss->rsize); seq_printf(m, ",wsize=%d", nfss->wsize); - if (nfss->acregmin != 3*HZ) + if (nfss->acregmin != 3*HZ || showdefaults) seq_printf(m, ",acregmin=%d", nfss->acregmin/HZ); - if (nfss->acregmax != 60*HZ) + if (nfss->acregmax != 60*HZ || showdefaults) seq_printf(m, ",acregmax=%d", nfss->acregmax/HZ); - if (nfss->acdirmin != 30*HZ) + if (nfss->acdirmin != 30*HZ || showdefaults) seq_printf(m, ",acdirmin=%d", nfss->acdirmin/HZ); - if (nfss->acdirmax != 60*HZ) + if (nfss->acdirmax != 60*HZ || showdefaults) seq_printf(m, ",acdirmax=%d", nfss->acdirmax/HZ); for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) { if (nfss->flags & nfs_infop->flag) @@ -633,8 +641,89 @@ static int nfs_show_options(struct seq_file *m, struct vfsmount *mnt) seq_printf(m, ",proto=%s", proto); seq_printf(m, ",timeo=%lu", 10U * nfss->retrans_timeo / HZ); seq_printf(m, ",retrans=%u", nfss->retrans_count); +} + +static int nfs_show_options(struct seq_file *m, struct vfsmount *mnt) +{ + struct nfs_server *nfss = NFS_SB(mnt->mnt_sb); + + nfs_show_mount_options(m, nfss, 0); + seq_puts(m, ",addr="); seq_escape(m, nfss->hostname, " \t\n\\"); + + return 0; +} + +static int nfs_show_stats(struct seq_file *m, struct vfsmount *mnt) +{ + int i, cpu; + struct nfs_server *nfss = NFS_SB(mnt->mnt_sb); + struct rpc_auth *auth = nfss->client->cl_auth; + struct nfs_iostats totals = { }; + + seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS); + + /* + * Display all mount option settings + */ + seq_printf(m, "\n\topts:\t"); + seq_puts(m, mnt->mnt_sb->s_flags & MS_RDONLY ? "ro" : "rw"); + seq_puts(m, mnt->mnt_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : ""); + seq_puts(m, mnt->mnt_sb->s_flags & MS_NOATIME ? ",noatime" : ""); + seq_puts(m, mnt->mnt_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : ""); + nfs_show_mount_options(m, nfss, 1); + + seq_printf(m, "\n\tcaps:\t"); + seq_printf(m, "caps=0x%x", nfss->caps); + seq_printf(m, ",wtmult=%d", nfss->wtmult); + seq_printf(m, ",dtsize=%d", nfss->dtsize); + seq_printf(m, ",bsize=%d", nfss->bsize); + seq_printf(m, ",namelen=%d", nfss->namelen); + +#ifdef CONFIG_NFS_V4 + if (nfss->rpc_ops->version == 4) { + seq_printf(m, "\n\tnfsv4:\t"); + seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]); + seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]); + seq_printf(m, ",acl=0x%x", nfss->acl_bitmask); + } +#endif + + /* + * Display security flavor in effect for this mount + */ + seq_printf(m, "\n\tsec:\tflavor=%d", auth->au_ops->au_flavor); + if (auth->au_flavor) + seq_printf(m, ",pseudoflavor=%d", auth->au_flavor); + + /* + * Display superblock I/O counters + */ + for (cpu = 0; cpu < NR_CPUS; cpu++) { + struct nfs_iostats *stats; + + if (!cpu_possible(cpu)) + continue; + + preempt_disable(); + stats = per_cpu_ptr(nfss->io_stats, cpu); + + for (i = 0; i < __NFSIOS_COUNTSMAX; i++) + totals.events[i] += stats->events[i]; + for (i = 0; i < __NFSIOS_BYTESMAX; i++) + totals.bytes[i] += stats->bytes[i]; + + preempt_enable(); + } + + seq_printf(m, "\n\tevents:\t"); + for (i = 0; i < __NFSIOS_COUNTSMAX; i++) + seq_printf(m, "%lu ", totals.events[i]); + seq_printf(m, "\n\tbytes:\t"); + for (i = 0; i < __NFSIOS_BYTESMAX; i++) + seq_printf(m, "%Lu ", totals.bytes[i]); + return 0; } @@ -1742,6 +1831,7 @@ static struct super_operations nfs4_sops = { .clear_inode = nfs4_clear_inode, .umount_begin = nfs_umount_begin, .show_options = nfs_show_options, + .show_stats = nfs_show_stats, }; /* @@ -2015,6 +2105,7 @@ out_err: out_free: kfree(server->mnt_path); kfree(server->hostname); + nfs_free_iostats(server->io_stats); kfree(server); return s; } diff --git a/fs/nfs/iostat.h b/fs/nfs/iostat.h new file mode 100644 index 00000000000000..dc080e50ec5733 --- /dev/null +++ b/fs/nfs/iostat.h @@ -0,0 +1,152 @@ +/* + * linux/fs/nfs/iostat.h + * + * Declarations for NFS client per-mount statistics + * + * Copyright (C) 2005, 2006 Chuck Lever + * + * NFS client per-mount statistics provide information about the health of + * the NFS client and the health of each NFS mount point. Generally these + * are not for detailed problem diagnosis, but simply to indicate that there + * is a problem. + * + * These counters are not meant to be human-readable, but are meant to be + * integrated into system monitoring tools such as "sar" and "iostat". As + * such, the counters are sampled by the tools over time, and are never + * zeroed after a file system is mounted. Moving averages can be computed + * by the tools by taking the difference between two instantaneous samples + * and dividing that by the time between the samples. + */ + +#ifndef _NFS_IOSTAT +#define _NFS_IOSTAT + +#define NFS_IOSTAT_VERS "1.0" + +/* + * NFS byte counters + * + * 1. SERVER - the number of payload bytes read from or written to the + * server by the NFS client via an NFS READ or WRITE request. + * + * 2. NORMAL - the number of bytes read or written by applications via + * the read(2) and write(2) system call interfaces. + * + * 3. DIRECT - the number of bytes read or written from files opened + * with the O_DIRECT flag. + * + * These counters give a view of the data throughput into and out of the NFS + * client. Comparing the number of bytes requested by an application with the + * number of bytes the client requests from the server can provide an + * indication of client efficiency (per-op, cache hits, etc). + * + * These counters can also help characterize which access methods are in + * use. DIRECT by itself shows whether there is any O_DIRECT traffic. + * NORMAL + DIRECT shows how much data is going through the system call + * interface. A large amount of SERVER traffic without much NORMAL or + * DIRECT traffic shows that applications are using mapped files. + * + * NFS page counters + * + * These count the number of pages read or written via nfs_readpage(), + * nfs_readpages(), or their write equivalents. + */ +enum nfs_stat_bytecounters { + NFSIOS_NORMALREADBYTES = 0, + NFSIOS_NORMALWRITTENBYTES, + NFSIOS_DIRECTREADBYTES, + NFSIOS_DIRECTWRITTENBYTES, + NFSIOS_SERVERREADBYTES, + NFSIOS_SERVERWRITTENBYTES, + NFSIOS_READPAGES, + NFSIOS_WRITEPAGES, + __NFSIOS_BYTESMAX, +}; + +/* + * NFS event counters + * + * These counters provide a low-overhead way of monitoring client activity + * without enabling NFS trace debugging. The counters show the rate at + * which VFS requests are made, and how often the client invalidates its + * data and attribute caches. This allows system administrators to monitor + * such things as how close-to-open is working, and answer questions such + * as "why are there so many GETATTR requests on the wire?" + * + * They also count anamolous events such as short reads and writes, silly + * renames due to close-after-delete, and operations that change the size + * of a file (such operations can often be the source of data corruption + * if applications aren't using file locking properly). + */ +enum nfs_stat_eventcounters { + NFSIOS_INODEREVALIDATE = 0, + NFSIOS_DENTRYREVALIDATE, + NFSIOS_DATAINVALIDATE, + NFSIOS_ATTRINVALIDATE, + NFSIOS_VFSOPEN, + NFSIOS_VFSLOOKUP, + NFSIOS_VFSACCESS, + NFSIOS_VFSUPDATEPAGE, + NFSIOS_VFSREADPAGE, + NFSIOS_VFSREADPAGES, + NFSIOS_VFSWRITEPAGE, + NFSIOS_VFSWRITEPAGES, + NFSIOS_VFSGETDENTS, + NFSIOS_VFSSETATTR, + NFSIOS_VFSFLUSH, + NFSIOS_VFSFSYNC, + NFSIOS_VFSLOCK, + NFSIOS_VFSRELEASE, + NFSIOS_CONGESTIONWAIT, + NFSIOS_SETATTRTRUNC, + NFSIOS_EXTENDWRITE, + NFSIOS_SILLYRENAME, + NFSIOS_SHORTREAD, + NFSIOS_SHORTWRITE, + __NFSIOS_COUNTSMAX, +}; + +#ifdef __KERNEL__ + +#include +#include + +struct nfs_iostats { + unsigned long long bytes[__NFSIOS_BYTESMAX]; + unsigned long events[__NFSIOS_COUNTSMAX]; +} ____cacheline_aligned; + +static inline void nfs_inc_stats(struct inode *inode, enum nfs_stat_eventcounters stat) +{ + struct nfs_iostats *iostats; + int cpu; + + cpu = get_cpu(); + iostats = per_cpu_ptr(NFS_SERVER(inode)->io_stats, cpu); + iostats->events[stat] ++; + put_cpu_no_resched(); +} + +static inline void nfs_add_stats(struct inode *inode, enum nfs_stat_bytecounters stat, unsigned long addend) +{ + struct nfs_iostats *iostats; + int cpu; + + cpu = get_cpu(); + iostats = per_cpu_ptr(NFS_SERVER(inode)->io_stats, cpu); + iostats->bytes[stat] += addend; + put_cpu_no_resched(); +} + +static inline struct nfs_iostats *nfs_alloc_iostats(void) +{ + return alloc_percpu(struct nfs_iostats); +} + +static inline void nfs_free_iostats(struct nfs_iostats *stats) +{ + free_percpu(stats); +} + +#endif +#endif diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h index a522ab97358dc5..d65e69a06b7237 100644 --- a/include/linux/nfs_fs_sb.h +++ b/include/linux/nfs_fs_sb.h @@ -4,6 +4,8 @@ #include #include +struct nfs_iostats; + /* * NFS client parameters stored in the superblock. */ @@ -12,6 +14,7 @@ struct nfs_server { struct rpc_clnt * client_sys; /* 2nd handle for FSINFO */ struct rpc_clnt * client_acl; /* ACL RPC client handle */ struct nfs_rpc_ops * rpc_ops; /* NFS protocol vector */ + struct nfs_iostats * io_stats; /* I/O statistics */ struct backing_dev_info backing_dev_info; int flags; /* various flags */ unsigned int caps; /* server capabilities */ -- cgit 1.2.3-korg