vxfsstat - display VxFS file system statistics

vxfsstat [ -aCgmsvxz ] [ -e columns ] [ -c count ]
[-t seconds ] mount_point

vxfsstat [ -abi ] [-c count ] [-t seconds ] mount_point

vxfsstat [ -w outfile ] [-c count ] [-t seconds ] mount_point

vxfsstat -r infile [ -aCvxz ] [ -e columns ]

VRTSvxfs

vxfsstat is a statistical reporter to aid in performance tuning and determining performance anomalies. vxfsstat gathers buffer cache, inode cache, DNLC (directory name lookup cache), per-CPU statistics, per-file system statistics for mounted file systems.

The mount_point specifies any VxFS file system mount point. mount_point is used as an ioctl entry point to access the statistics maintained by the VxFS kernel.

The vxfsstat command was introduced to provide a diagnostic and tuning tool for knowledgeable VxFS file system users. The command is still under development and may undergo significant additions and changes. There is a strong possibility that functionality introduced and modified in future versions will not be completely backward compatible. Take this into account when you begin using this command and incorporating it into scripts. As an alternative, consider using the static interfaces vxfsu_get_bc_counters and vxfsu_get_dnlc_counter. These APIs are in the vxfsutil.h header file.

Some options can be used only on cluster mounted file systems. Read the option descriptions for details on whether the option is valid for local mounts.

-a	Displays absolute values.
-b	Displays global buffer cache statistics. vxfsstat displays the following counters: Kbyte current   The memory in kilobytes that are consumed by the VxFS metadata buffer cache. maximum   The maximum memory in kilobytes that the VxFS metadata buffer cache can consume. lookups   The count of read requests for a buffer that may be read from the disk if not incore. % hit rate   Hit rate is defined as a percentage of successful buffer lookups (total - misses) with respect to total lookups. A miss is counted when a buffer read request fails if memory is unavailable and it is a non-blocking request. sec recycle age   The average age (in seconds) of the recycled buffer.
-c count	Specifies the number of samples to take.
-C	Displays per-CPU statistics.
-e columns	Selects the number of column entries to display per line of output. The default is two columns. -e does not affect all output formats.
-g	Displays cluster file system global statistics. Not valid on non-cluster (local) mounted file systems.
-i	Displays global inode cache and DNLC statistics. -i is the default output format. vxfsstat displays the following counters: maximum entries in dnlc   The maximum number of DNLC entries. total lookups   The total number of actual directory lookups. % fast lookup   The percentage of fast directory lookups with respect to the total directory lookups. total dnlc lookup   The total number of DNLC lookups. The value is the sum of the total number of DNLC hits (positive and negative) and DNLC misses. % dnlc hit rate   The percentage of total DNLC hits (positive and negative) with respect to the total DNLC lookup. total enter   The number of times that a positive DNLC entry was entered into the DNLC. hit per enter   The number of total DNLC hits (positive and negative) per DNLC enter (positive and negative). total dircache setup   The count of directory cache setup. calls per setup   The number of directory cache calls, including dircache name and space hits and misses, per dircache setup. total directory scan   The number of times that a directory was scanned while looking for a name or space to hold a name. The value is the sum of normal directory scans and fast directory scans. % fast directory scan   The percentage of fast directory scans to the total number of directory scans. inodes current   The current number of incore inodes. peak The maximum number of inodes that were brought incore since system startup. The value is the maximum recorded value of current inodes. maximum   The maximum number of inodes that can be brought incore, which is equal to the inode cache size. VxFS limits the number of incore inodes to this value. lookups   The number of times iget was called while looking for an inode. % hit rate   The percentage of inodes that were found incore with respect to the total number of inodes looked up. inodes alloced   The total number of inodes for which memory was allocated since system startup. freed   The total number of inodes that were freed. This is the memory for inodes that were de-allocated. The difference between this counter and inodes alloced is that freed gives the current number of incore inodes. recycle age   The average age (in seconds) of recycled inodes. free age   The maximum length of time that you want inodes to be on the free-list. If inodes are staying on the free-list for more than this time, then the inode table size is reduced.
-m	Displays counters, in units of bytes, showing the current pinned memory usage by VxFS. The following counters are displayed: Total Allocated   Displays the pinned memory currently in use by the VxFS driver. Inode cache   Displays pinned memory usage associated with the VxFS inode cache. Buffer cache   Displays pinned memory usage associated with the VxFS metadata buffer cache. -r infile Replays output from the specified file infile. You can create output files using the -w option. -v Displays VxFS shared counters and statistics. -s Displays per-file system statistics for cluster file systems. Not valid on non-cluster (local) mounted file systems. -t seconds Specifies the duration of the sampling interval in seconds. -w outfile Appends output to the specified file outfile. vxfsstat can be invoked multiple times with the same file to collect multiple samples. The -w option can only be used with the -c and -t options. -x Displays per-file system VxFS statistics. -z Displays only non-zero values.

The following examples show the output of vxfsstat using various options. The following command displays buffer cache statistics:

# vxfsstat -b -c 5 /mount_point


0:43:44.091  Mon Apr 15 2002 -- absolute sample


buffer cache statistics
    36992 Kbyte current      377456 maximum       
688187425 lookups            99.98% hit rate      
    37165 sec reuse age [not limited by maximum]


10:43:54.121  Mon Apr 15 2002 -- delta (10.029 sec sample)


buffer cache statistics
    36992 Kbyte current      377456 maximum       
    29793 lookups            99.10% hit rate      
    37175 sec reuse age [not limited by maximum]


10:44:04.131  Mon Apr 15 2002 -- delta (10.010 sec sample)


buffer cache statistics
    36992 Kbyte current      377456 maximum       
    29199 lookups            99.15% hit rate      
    37185 sec reuse age [not limited by maximum]

The following command displays shared counters and statistics kept by VxFS:

# vxfsstat -v  /mount_point


10:49:10.791  Mon Apr 15 2002 -- absolute sample


vxi_alloc_emap          127699050  vxi_alloc_expand_retry   891125
vxi_alloc_find_retry       153857  vxi_alloc_findfail    225394263
vxi_alloc_findfix          889319  vxi_alloc_mapflush            2
vxi_alloc_prev           14581575  vxi_alloc_search       59147260
vxi_alloc_smap                  0  vxi_alloc_sumclean            0