NAME
vxstat — Volume Manager statistics management utility
SYNOPSIS
vxstat
[-dpsv ]
[-f fields ]
[-g diskgroup]
[-i interval [ -c count ]]
[-n node [,node...]]
[-r ]
[object...]
DESCRIPTION
The
vxstat
utility prints and resets statistics information on one
or more volumes, plexes, subdisks, or disks.
The vxstat utility reads statistics from the volume
device files in the directory /dev/vx/rdsk and prints
them to standard output. These statistics represent
volume, plex, subdisk, and disk activity since boot time.
If no object operands are given, then statistics from
all volumes in the configuration database are reported.
object can be the name of a volume, plex, subdisk, or
disk.
In a Volume Manager cluster environment,
vxstat
gathers the requested statistics from all nodes in the cluster,
and reports the aggregate totals. You can specify a node list
to indicate a subset of nodes from which to gather statistics.
OPTIONS
- -c count
Stop after printing interval statistics count times.
- -d
Display statistics for disks on which the
object
specified on the command line is fully or partially located.
- -f fields
Select the display of statistics collected. The following options
are available:
- 0 | O
Statistics for the VOL_R5_ZERO operation. Each operation represents
one call to the VOL_R5_ZERO ioctl. The number of blocks is based on
the number of zeroed blocks written to the array. The average time is the
time taken to complete the entire ioctl operation.
- a
Statistics on atomic copies performed
(has meaning only for mirrored volumes).
Displays the number of operations, number of blocks, and
the average time spent per operation.
- b
Displays the statistics on read-writeback mirror consistency recovery
operations (has meaning only for mirrored volumes). Displays three fields:
the number of read-writeback operations,
the number of blocks involved in read-writeback operations,
and the average time for completing a read-writeback operation.
While in recovery mode, most read operations to a mirrored volume
invoke read-writeback consistency recovery.
- c
Statistics on corrected (fixed) read operations
(has meaning only for mirrored or RAID-5 volumes).
Displays the number of fixed read and write operations.
Note: Currently, only read operations are ever corrected, so the
number of fixed writes will always be zero.
- C
Statistics for the VOL_R5_RECOVER operation. Each operation
count represents one call to the VOL_R5_RECOVER ioctl. The number
of blocks represents the resulting number of blocks that were written
to the missing column region as part of the data recovery. The
read operations are not counted towards the total.
- f
Displays the number of failed read and write operations.
- F
Statistics for full-stripe writes on a RAID-5 volume. The number
of operations represents the number of write operations within a
stripe that were conducted as a full-stripe write optimization.
Full-stripe writes represent considerably less overhead than
read-modify-writes in terms of overall I/O time, latency and CPU
overhead. The total number of blocks represents the total size of the
written data and the average time is the time taken for a full-stripe write
operation. Since the I/O may be larger then a single stripe, more than one
stripe operation may be seen for a single logical I/O request.
- M
Read-modify-write statistics. Each operation represents a read-modify write
operation performed within a stripe. I/O crossing a stripe boundary will be
represented by more than a single read-modify write operation. The number
of blocks counted represents only the size of the requested write. The
read portion of the I/O can be derived.
- R
Reconstruct read operations. Each operation is a separate reconstruct read
operation. A single stripe read or write operation can lead to numerous
reconstruct read operations since each reconstruction takes place at the
subdisk level. A detached column can consist of several subdisks each of
which will lead to a reconstruct read operation.
- s
Statistics on read and write operations.
Displays six fields:
the number of read operations, the number of write operations,
the number of blocks read, the number of blocks written,
the average time spent on read operations in the interval,
and the average time spent on write operations in the interval.
These statistics are displayed as the default output format.
- S
Statistics for the VOL_R5_RESYNC operation. Each operation
count represents one call to the VOL_R5_RESYNC ioctl. The number
of blocks represents the resulting number of blocks that were written
to the parity regions as part of the resynchronization of parity. The
read operations are not counted towards the total.
- v
Statistics on verified reads and writes
(has meaning only for mirrored volumes).
Displays six fields:
the number of verified read operations,
the number of verified write operations,
the number of blocks read, the number of blocks written,
the average time spent on verified read operations in the interval,
and the average time spent on verified write operations in the interval.
- V
Statistics for the VOL_R5_VERIFY operation. Each operation
count represents one call to the VOL_R5_VERIFY ioctl. The number
of blocks represents the resulting number of blocks that were read
as part of the RAID-5 stripes consistency verification.
- W
Reconstruct write statistics. Each operation counted is for a reconstruct
write operation performed as an optimization of a write operation within
a stripe. The number of blocks counted represents the count of data blocks
written not including parity or read operations.
- -g diskgroup
Select records from the specified disk group. The diskgroup
option argument can be either a disk group name or disk group ID.
- -i interval
Print the change in volume statistics that occurs after
every interval seconds. The first interval is
assumed to encompass the entire previous history of
objects. Subsequent displays will show statistics with a zero
value if there has been no change since the previous interval.
- -n node[,node...]
Gathers and displays statistics for the nodes specified in
node, where node is a comma separated list of
integer node numbers.
- -p
Display statistics for plexes on the
object
specified on the command line.
For subdisk
objects,
displays information about a plex with which it is
associated.
- -r
Reset statistics instead of printing them. This option will
follow the same selection rules as printing
for any type selection arguments or for any named objects. If
an interval was specified on the command line, then the first
set of statistics will not be printed since they will have
been reset to zero.
Subsequent activity will cause printing of statistics as normal.
- -s
Display statistics for subdisks on the
objects
specified on the
command line.
- -v
Display statistics for volumes on the objects
specified on the command line. For an object that is
a plex or a subdisk, displays information about the volume
with which the object is associated. If an
object supplied is a disk, then any volumes that
occupy any part of the disk will be selected.
OUTPUT FORMAT
Summary statistics for each object are printed in one-line output
records, preceded by two header lines.
The output line consists of
blank-separated fields for the object type, object name (standard), and
the fields requested by the
-f
switch in the order they are specified on the command line.
If the -i interval option was supplied, then statistics will be
prefaced with a time-stamp showing the current local time on the system.
EXIT CODES
The
vxstat
utility 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
further execution of the utility.
See
vxintro(1M)
for a list of standard exit codes.
EXAMPLES
To display statistics for all subdisks associated with all
volumes, use the command:
To display statistics for the plexes and subdisks of a volume named blop,
use the following:
To reset all statistics for a disk group named foodg, type the following
command:
To display 5 sets of disk statistics at 10 second intervals, use the following:
Printable version
