fiostat(1)fiostat(1)NAMEfiostat - VxFS file I/O statistics utility
AVAILABILITY
VRTSvxfs
SYNOPSIS
/opt/VRTS/bin/fiostat on [ -o offset] [ -l length] -n nsubfiles file‐
name
/opt/VRTS/bin/fiostat off filename
/opt/VRTS/bin/fiostat reset filename
/opt/VRTS/bin/fiostat getconfig filename
/opt/VRTS/bin/fiostat dump [ -i interval [ -c count] ] -r filename
DESCRIPTION
The fiostat command prints and resets file and sub-file I/O statistics,
turns on and off sub-file I/O statistics, and gets sub-file statistic
configuration values. filename can be the pathname of a regular file
or a QIO file. The file name extension ::cdev:vxfs: is required for a
QIO file.
The fiostat command reads file-level I/O statistics for the specified
file and prints the statistics to standard output. If sub-file statis‐
tics are turned on, fiostat reads and prints statistics for the
sub-file units. These statistics show I/O activity since the file's
last close or since the previous statistics reset.
Cluster File System Issues
This command works on a local node, only.
KEYWORDS
on Turns on sub-file statistics for the specified file. If it
is already on, current statistics are reset to zero and the
configuration is set to the specified values.
off Turns off sub-file statistics for the specified file. No
action is taken if the sub-file statistics are already turned
off.
reset Resets statistics to zero.
getconfig Prints the current configuration values, offset, length, and
nsubfiles, to standard output if sub-file statistics are
turned on. When sub-file statistics are turned off, fiostat
prints zeroes.
dump Prints file statistics for the specified file to standard
output. If sub-file statistics are turned on, fiostat prints
the statistics to standard output.
OPTIONS-c count The fiostat command stops after printing statistics count
times.
-i interval
Prints current I/O statistics every interval seconds.
-l length Specifies the total length of sub-file units in bytes. The
length can be specified in kilobytes, megabytes, gigabytes,
or terabytes by appending k, m, g, or t. The default length
is the file's current size.
-o offset Specifies the file offset in bytes where the first sub-file
unit starts. The offset can be specified in kilobytes,
megabytes, gigabytes, or terabytes by appending k, m, g, or
t. The default offset is zero.
-n nsubfiles
Specifies the number of sub-file units to monitor. The num‐
ber must be a non-zero value less than 1024. 1024 is the
maximum number of sub-file units allowed per file.
-r Resets statistics to zero after each print.
OUTPUT FORMAT
I/O statistics are printed in a single line output record preceded by
the file's name, the current local time on the system, the time when
statistics were reset last, and two header lines. The output line con‐
sists of blank-separated fields for the object type (file or subfile),
and statistics on read and write operations:
· Number of read operations
· Number of write operations
· Number of bytes read
· Number of bytes written
· Average time spent on read operations
· Average time spent on write operations
Sub-file statistics do not include average time spent on read and write
operations.
The following is sample output of a file-level-only statistics dump:
File Name: /mnt/foo
Current time: Wed 28 Sep 2005 01:08:33 PM PDT
Reset time: Wed 28 Sep 2005 01:06:33 PM PDT
FILE/SUBFILE OPERATIONS BYTES AVG TIME(ms)
READ WRITE READ WRITE READ WRITE
file 341 348 34926 35699 4.1 4.5
The following is sample output of a file and sub-file statistics dump:
File Name: /mnt/foo
Current time: Wed 28 Sep 2005 01:08:33 PM PDT
Reset time: Wed 28 Sep 2005 01:06:33 PM PDT
FILE/SUBFILE OPERATIONS BYTES AVG TIME(ms)
READ WRITE READ WRITE READ WRITE
file 341 348 34926 35699 4.1 4.5
subfile1 27 24 2780 2434
subfile2 27 28 2744 2813
subfile3 27 28 2767 2808
subfile4 25 26 2552 2634
If the -i interval option is supplied, statistics are prefaced with two
time stamps showing the current local time on the system and when sta‐
tistics were reset last.
The following is sample output of a file and sub-file statistics dump
with -i 3 -c 3 specified:
File Name: /mnt/foo
FILE/SUBFILE OPERATIONS BYTES AVG TIME(ms)
READ WRITE READ WRITE READ WRITE
Current time: Wed 28 Sep 2005 12:56:40 PM PDT
Reset time: Wed 28 Sep 2005 12:51:50 PM PDT
file 297 301 30426 30918 4.1 4.5
subfile1 24 19 2503 1984
subfile2 24 23 2447 2398
subfile3 24 24 2439 2467
subfile4 21 22 2122 2293
Current time: Wed 28 Sep 2005 12:56:45 PM PDT
Reset time: Wed 28 Sep 2005 12:51:50 PM PDT
file 322 324 33074 33746 4.1 4.5
subfile1 26 22 2677 2204
subfile2 26 26 2626 2664
subfile3 26 26 2680 2695
subfile4 23 24 2368 2490
Current time: Wed 28 Sep 2005 12:56:50 PM PDT
Reset time: Wed 28 Sep 2005 12:51:50 PM PDT
file 341 348 34926 35699 4.1 4.5
subfile1 27 24 2780 2434
subfile2 27 28 2744 2813
subfile3 27 28 2767 2808
subfile4 25 26 2552 2634
EXIT CODESfiostat exits with a non-zero status if the attempted operation fails.
A non-zero exit code is not a complete indicator of the problems
encountered, but rather denotes the first condition that prevented fur‐
ther execution of the command.
EXAMPLES
To display statistics for file /mnt/foo, which does not have sub-file
statistics turned on:
# fiostat dump /mnt/foo
To turn on sub-file statistics for file /mnt/foo and monitor the file
from offset 1024 to offset 1024+8129=9153 in 10 sub-file units:
# fiostat on -o 1024 -l 8129 -n 10 /mnt/foo
To display statistics for file /mnt/foo 8 times at 5-second interval:
fiostat dump -i 5 -c 8 /mnt/foo
SEE ALSOvxfs_fiostats_dump(3), vxfs_fiostats_getconfig(3), vxfs_fiostats_set(3)VxFS 5.0 7 Jan 2008 fiostat(1)
