Veritas™ Volume Manager Administrator's Guide

Examples of using the vxdmpadm iostat command

The following is an example session using the vxdmpadm iostat command. The first command enables the gathering of I/O statistics:

# vxdmpadm iostat start

The next command displays the current statistics including the accumulated total numbers of read and write operations and kilobytes read and written, on all paths:

# vxdmpadm iostat show all
                     cpu usage = 7952us    per cpu memory = 8192b
             OPERATIONS            KBYTES             AVG TIME(ms)
PATHNAME  READS     WRITES    READS     WRITES     READS   WRITES
c0t0d0     1088          0   557056          0      0.00     0.00
c2t118d0     87          0    44544          0      0.00     0.00
c3t118d0      0          0        0          0      0.00     0.00
c2t122d0     87          0    44544          0      0.00     0.00
c3t122d0      0          0        0          0      0.00     0.00
c2t115d0     87          0    44544          0      0.00     0.00
c3t115d0      0          0        0          0      0.00     0.00
c2t103d0     87          0    44544          0      0.00     0.00
c3t103d0      0          0        0          0      0.00     0.00
c2t102d0     87          0    44544          0      0.00     0.00
c3t102d0      0          0        0          0      0.00     0.00
c2t121d0     87          0    44544          0      0.00     0.00
c3t121d0      0          0        0          0      0.00     0.00
c2t112d0     87          0    44544          0      0.00     0.00
c3t112d0      0          0        0          0      0.00     0.00
c2t96d0      87          0    44544          0      0.00     0.00
c3t96d0       0          0        0          0      0.00     0.00
c2t106d0     87          0    44544          0      0.00     0.00
c3t106d0      0          0        0          0      0.00     0.00
c2t113d0     87          0    44544          0      0.00     0.00
c3t113d0      0          0        0          0      0.00     0.00
c2t119d0     87          0    44544          0      0.00     0.00
c3t119d0      0          0        0          0      0.00     0.00

The following command changes the amount of memory that vxdmpadm can use to accumulate the statistics:

# vxdmpadm iostat start memory=4096

The displayed statistics can be filtered by path name, DMP node name, and enclosure name (note that the per-CPU memory has changed following the previous command):

# vxdmpadm iostat show pathname=c3t115d0
                   cpu usage = 8132us    per cpu memory = 4096b
             OPERATIONS           BYTES           AVG TIME(ms)
PATHNAME  READS     WRITES    READS     WRITES   READS   WRITES
c3t115d0      0          0        0          0    0.00     0.00

# vxdmpadm iostat show dmpnodename=c0t0d0
                   cpu usage = 8501us    per cpu memory = 4096b
              OPERATIONS           BYTES           AVG TIME(ms)
PATHNAME  READS     WRITES    READS     WRITES   READS   WRITES
c0t0d0     1088          0   557056          0    0.00     0.00

# vxdmpadm iostat show enclosure=Disk
                   cpu usage = 8626us    per cpu memory = 4096b
             OPERATIONS           BYTES           AVG TIME(ms)
PATHNAME   READS     WRITES    READS     WRITES   READS   WRITES
c0t0d0     1088          0    557056          0    0.00     0.00

You can also specify the number of times to display the statistics and the time interval. Here the incremental statistics for a path are displayed twice with a 2-second interval:

# vxdmpadm iostat show pathname=c3t115d0 interval=2 count=2
                   cpu usage = 8195us    per cpu memory = 4096b
             OPERATIONS           BYTES           AVG TIME(ms)
PATHNAME  READS     WRITES    READS     WRITES   READS   WRITES
c3t115d0      0          0        0          0    0.00     0.00

                 cpu usage = 59us    per cpu memory = 4096b
             OPERATIONS           BYTES           AVG TIME(ms)
PATHNAME  READS     WRITES    READS     WRITES   READS   WRITES
c3t115d0      0          0        0          0    0.00     0.00