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review.evervolv.com / android_kernel_htc_msm8960 / 7e8970e1d5ae9237d00909599e70f85fce1fc489 / . / include / linux / nfs_iostat.h
blob: 68b10f5f8907fe0517d0bc5352686b34dd5be9e3 [file] [log] [blame]
Chuck Lever34e8f922008-06-12 12:32:25 -0400[diff] [blame]1/*
2 * User-space visible declarations for NFS client per-mount
3 * point statistics
4 *
5 * Copyright (C) 2005, 2006 Chuck Lever <cel@netapp.com>
6 *
7 * NFS client per-mount statistics provide information about the
8 * health of the NFS client and the health of each NFS mount point.
9 * Generally these are not for detailed problem diagnosis, but
10 * simply to indicate that there is a problem.
11 *
12 * These counters are not meant to be human-readable, but are meant
13 * to be integrated into system monitoring tools such as "sar" and
14 * "iostat". As such, the counters are sampled by the tools over
15 * time, and are never zeroed after a file system is mounted.
16 * Moving averages can be computed by the tools by taking the
17 * difference between two instantaneous samples and dividing that
18 * by the time between the samples.
19 */
20
21#ifndef _LINUX_NFS_IOSTAT
22#define _LINUX_NFS_IOSTAT
23
24#define NFS_IOSTAT_VERS "1.0"
25
26/*
27 * NFS byte counters
28 *
29 * 1. SERVER - the number of payload bytes read from or written
30 * to the server by the NFS client via an NFS READ or WRITE
31 * request.
32 *
33 * 2. NORMAL - the number of bytes read or written by applications
34 * via the read(2) and write(2) system call interfaces.
35 *
36 * 3. DIRECT - the number of bytes read or written from files
37 * opened with the O_DIRECT flag.
38 *
39 * These counters give a view of the data throughput into and out
40 * of the NFS client. Comparing the number of bytes requested by
41 * an application with the number of bytes the client requests from
42 * the server can provide an indication of client efficiency
43 * (per-op, cache hits, etc).
44 *
45 * These counters can also help characterize which access methods
46 * are in use. DIRECT by itself shows whether there is any O_DIRECT
47 * traffic. NORMAL + DIRECT shows how much data is going through
48 * the system call interface. A large amount of SERVER traffic
49 * without much NORMAL or DIRECT traffic shows that applications
50 * are using mapped files.
51 *
52 * NFS page counters
53 *
54 * These count the number of pages read or written via nfs_readpage(),
55 * nfs_readpages(), or their write equivalents.
56 *
57 * NB: When adding new byte counters, please include the measured
58 * units in the name of each byte counter to help users of this
59 * interface determine what exactly is being counted.
60 */
61enum nfs_stat_bytecounters {
62 NFSIOS_NORMALREADBYTES = 0,
63 NFSIOS_NORMALWRITTENBYTES,
64 NFSIOS_DIRECTREADBYTES,
65 NFSIOS_DIRECTWRITTENBYTES,
66 NFSIOS_SERVERREADBYTES,
67 NFSIOS_SERVERWRITTENBYTES,
68 NFSIOS_READPAGES,
69 NFSIOS_WRITEPAGES,
70 __NFSIOS_BYTESMAX,
71};
72
73/*
74 * NFS event counters
75 *
76 * These counters provide a low-overhead way of monitoring client
77 * activity without enabling NFS trace debugging. The counters
78 * show the rate at which VFS requests are made, and how often the
79 * client invalidates its data and attribute caches. This allows
80 * system administrators to monitor such things as how close-to-open
81 * is working, and answer questions such as "why are there so many
82 * GETATTR requests on the wire?"
83 *
84 * They also count anamolous events such as short reads and writes,
85 * silly renames due to close-after-delete, and operations that
86 * change the size of a file (such operations can often be the
87 * source of data corruption if applications aren't using file
88 * locking properly).
89 */
90enum nfs_stat_eventcounters {
91 NFSIOS_INODEREVALIDATE = 0,
92 NFSIOS_DENTRYREVALIDATE,
93 NFSIOS_DATAINVALIDATE,
94 NFSIOS_ATTRINVALIDATE,
95 NFSIOS_VFSOPEN,
96 NFSIOS_VFSLOOKUP,
97 NFSIOS_VFSACCESS,
98 NFSIOS_VFSUPDATEPAGE,
99 NFSIOS_VFSREADPAGE,
100 NFSIOS_VFSREADPAGES,
101 NFSIOS_VFSWRITEPAGE,
102 NFSIOS_VFSWRITEPAGES,
103 NFSIOS_VFSGETDENTS,
104 NFSIOS_VFSSETATTR,
105 NFSIOS_VFSFLUSH,
106 NFSIOS_VFSFSYNC,
107 NFSIOS_VFSLOCK,
108 NFSIOS_VFSRELEASE,
109 NFSIOS_CONGESTIONWAIT,
110 NFSIOS_SETATTRTRUNC,
111 NFSIOS_EXTENDWRITE,
112 NFSIOS_SILLYRENAME,
113 NFSIOS_SHORTREAD,
114 NFSIOS_SHORTWRITE,
115 NFSIOS_DELAY,
116 __NFSIOS_COUNTSMAX,
117};
118
David Howells6a510912009-04-03 16:42:43 +0100[diff] [blame]119/*
120 * NFS local caching servicing counters
121 */
122enum nfs_stat_fscachecounters {
123 NFSIOS_FSCACHE_PAGES_READ_OK,
124 NFSIOS_FSCACHE_PAGES_READ_FAIL,
125 NFSIOS_FSCACHE_PAGES_WRITTEN_OK,
126 NFSIOS_FSCACHE_PAGES_WRITTEN_FAIL,
127 NFSIOS_FSCACHE_PAGES_UNCACHED,
128 __NFSIOS_FSCACHEMAX,
129};
130
Chuck Lever34e8f922008-06-12 12:32:25 -0400[diff] [blame]131#endif /* _LINUX_NFS_IOSTAT */