kernel-ark/include/linux/nfs_iostat.h
Andy Adamson 15a4520621 SUNRPC: add sending,pending queue and max slot to xprt stats
With static RPC slots, the xprt backlog queue stats were useful in showing
when the transport (TCP) was starved by lack of RPC slots. The new dynamic
RPC slot code, commit d9ba131d8f, always
provides an RPC slot and so only uses the xprt backlog queue when the
tcp_max_slot_table_entries value has been hit or when an allocation error
occurs. All requests are now placed on the xprt sending or pending queue which
need to be monitored for debugging.

The max_slot stat shows the maximum number of dynamic RPC slots reached which is
useful when debugging performance issues.

Add the new fields at the end of the mountstats xprt stanza so that mountstats
outputs the previous correct values and ignores the new fields. Bump
NFS_IOSTATS_VERS.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-02-16 14:55:27 -05:00

134 lines
4.1 KiB
C

/*
* User-space visible declarations for NFS client per-mount
* point statistics
*
* Copyright (C) 2005, 2006 Chuck Lever <cel@netapp.com>
*
* 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 _LINUX_NFS_IOSTAT
#define _LINUX_NFS_IOSTAT
#define NFS_IOSTAT_VERS "1.1"
/*
* 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.
*
* NB: When adding new byte counters, please include the measured
* units in the name of each byte counter to help users of this
* interface determine what exactly is being counted.
*/
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_DELAY,
NFSIOS_PNFS_READ,
NFSIOS_PNFS_WRITE,
__NFSIOS_COUNTSMAX,
};
/*
* NFS local caching servicing counters
*/
enum nfs_stat_fscachecounters {
NFSIOS_FSCACHE_PAGES_READ_OK,
NFSIOS_FSCACHE_PAGES_READ_FAIL,
NFSIOS_FSCACHE_PAGES_WRITTEN_OK,
NFSIOS_FSCACHE_PAGES_WRITTEN_FAIL,
NFSIOS_FSCACHE_PAGES_UNCACHED,
__NFSIOS_FSCACHEMAX,
};
#endif /* _LINUX_NFS_IOSTAT */