sar(1) BSD General Commands Manual sar(1)NAMEsar — system activity reporter
SYNOPSISsar [-dgpu] [-n mode] [-o filename] t [n]
sar [-dgpu] [-n mode] [-e time] [-f filename] [-i seconds] [-s time]
The sar command is used to sample and report various cumulative statistic
counters maintained by the operating system. It can be invoked in two
In the first usage instance, n samples are reported at t second inter‐
vals. If n is not specified, only one sample will be captured. When the
-o option is specified, sar will write the binary sampling data to the
output file specified by filename.
In the second usage instance, there is no on-going sample interval to
specify. This is because the sampling input comes from a previously
recorded, binary activity file. The binary activity file can be speci‐
fied using the -f filename option. When the -f option isn't used, sar
attempts to open a default binary activity file, /var/log/sa/sadd, where
dd represents the current day of the month. The starting and ending time
of the report can be restricted using the -e and -s options. Here, the
time field is specified in the form hh[:mm[:ss]]. Finally, the -i option
can be used to select the sampling interval. Only records at least
seconds apart will be reported. When the -i option is not used, all of
the previously recorded interval samples are reported.
Due to the nature of on-going sample collection, the data is reported in
a verbose mode when more than one sampling option is specified. Column
headers are printed at the beginning of the report and averages are
printed when the sar command terminates.
The following options restrict the sample set that sar reports.
-d Report disk activity.
device The BSD name of the device.
r+w/s The number of reads and writes per second.
blks/s Number of blocks (in device's default blocksize) trans‐
ferred to a device per second.
-g Report page-out activity.
pgout/s The number of pages paged out per second.
-p Report page-in and page fault activity
pgin/s The number of pages paged in per second.
pflts/s The number of faults that caused a page to be copied in
vflts/s The number of times vm_fault routine has been called.
-n mode Report network activity with modes DEV, EDEV, or PPP. Multiple
network modes can be specified.
DEV The DEV mode reports network device statistics. The
following information is displayed for each interface.
IFACE The network interface name.
Ipkts/s The number of packets received per second.
Ibytes/s The number of bytes received per second.
Opkts/s The number of packets sent per second.
Obytes/s The number of bytes sent per second.
EDEV The EDEV mode reports network device error statistics.
The following information is displayed for each inter‐
IFACE The interface name.
Ierrs/s The input errors per second.
Oerrs/s The output errors per second.
Coll/s The collisions that occurred per second.
Drops/s The number of dropped packets per second.
PPP The PPP mode must be specified in order to display ppp
connections in the network statistics. This will also
turn on the PPP modify mode in sadc (8) when sampling
data is not being read from a file. By default, both
the collection and reporting of ppp statistics is
turned off. See sadc (8).
-u Report CPU activity (default)
%usr, %sys, and %idle
These report the percentage of time running in user mode, system
mode and idle.
/var/log/sa/sadd Default daily activity file that holds the binary sam‐
pling data. dd are digits that represent the day of
SEE ALSOsa1(8), sa2(8), sadc(8), iostat(8), vm_stat(1), netstat(1), top(1),
sc_usage(1), fs_usage(1)Mac OS X Jul 25, 2003 Mac OS X