4 sa

sa summarizes information about previously executed commands as recorded in the acct file. In addition, it condenses this data into the savacct summary file, which contains the number of times the command was called and the system resources used. The information can also be summarized on a per-user basis; sa will save this information into usracct. Usage:

sa [opts] [file]

If no arguments are specified, sa will print information about all of the commands in the acct file. If command names have unprintable characters, or are only called once, sa will sort them into a group called ***other. Overall totals for each field are gathered and printed with a blank command name.

If called with a file name as the last argument, sa will use that file instead of acct.

By default, sa will sort the output by sum of user and system time.

The output fields are labeled as follows:

cpu

sum of system and user time in cpu seconds

re

“real time” in cpu seconds

k

cpu-time averaged core usage, in 1k units

avio

average number of I/O operations per execution

tio

total number of I/O operations

k*sec

cpu storage integral (kilo-core seconds)

u

user cpu time in cpu seconds

s

system time in cpu seconds

Note that these column titles do not appear in the first row of the table, but after each numeric entry (as units of measurement) in every row. For example, you might see 79.29re, meaning 79.29 cpu seconds of “real time.”

An asterisk will appear after the name of commands that forked but didn’t call exec.

4.1 Flags

The availability of these program options depends on your operating system. In specific, the members that appear in the struct acct of your system’s process accounting header file (usually acct.h) determine which flags will be present. For example, if your system’s struct acct doesn’t have the ac_mem field, the installed version of sa will not support the --sort-cpu-avmem, --sort-ksec, -k, or -K options.

In short, all of these flags may not be available on your machine.

-a

--list-all-names

Force sa not to sort those command names with unprintable characters and those used only once into the ‘***other’ group.

-b

--sort-sys-user-div-calls

Sort the output by the sum of user and system time divided by the number of calls.

-c

--percentages

Print percentages of total time for the command’s user, system, and real time values.

-d

--sort-avio

Sort the output by the average number of disk I/O operations.

-D

--sort-tio

Print and sort the output by the total number of disk I/O operations.

-f

--not-interactive

When using the --threshold option, assume that all answers to interactive queries will be affirmative.

-i

--dont-read-summary-file

Don’t read the information in savacct.

-j

--print-seconds

Instead of printing total minutes for each category, print seconds per call.

-k

--sort-cpu-avmem

Sort the output by cpu time average memory usage.

-K

--sort-ksec

Print and sort the output by the cpu-storage integral.

-l

--separate-times

Print separate columns for system and user time; usually the two are added together and listed as cpu.

-m

--user-summary

Print the number of processes and number of CPU minutes on a per-user basis.

-n

--sort-num-calls

Sort the output by the number of calls. This is the default sorting method.

-p

--show-paging

Print the number of minor and major pagefaults and swaps.

-P

--show-paging-avg

Print the number of minor and major pagefaults and swaps divided by the number of calls.

-r

--reverse-sort

Sort output items in reverse order.

-s

--merge

Merge the summarized accounting data into the summary files savacct and usracct.

-t

--print-ratio

For each entry, print the ratio of real time to the sum of system and user times. If the sum of system and user times is too small to report—the sum is zero—*ignore* will appear in this field.

-u

--print-users

For each command in the accounting file, print the userid and command name. After printing all entries, quit. Note: this flag supersedes all others.

-v num

--threshold num

Print commands which were executed num times or fewer and await a reply from the terminal. If the response begins with y, add the command to the **junk** group.

--separate-forks

It really doesn’t make any sense to me that the stock version of sa separates statistics for a particular executable depending on whether or not that command forked. Therefore, GNU sa lumps this information together unless this option is specified.

--sort-real-time

Sort the output by the “real time” (elapsed time) for each command.

--ahz hz

Use this flag to tell the program what AHZ should be (in hertz). This option is useful if you are trying to view an acct file created on another machine which has the same byte order and file format as your current machine, but has a different value for AHZ.

--debug

Print verbose internal information.

-V

--version

Print sa’s version number.

-h

--help

Print sa’s usage string and default locations of system files to standard output.

Note: if more than one sorting option is specified, the list will be sorted by the one specified last on the command line.

4.2 Problems

I haven’t been able to test this on many different machines because the data files grow so big in a short time; our sysadmin would rather save the disk space.

Most versions of sa that I’ve tested don’t pay attention to flags like --print-seconds and --sort-num-calls when printing out commands when combined with the --user-summary or --print-users flags. GNU sa pays attention to these flags if they are applicable.

4.2.1 mips sa

The average memory use is stored as a short rather than a double, so we suffer from round-off errors. GNU sa uses double the whole way through.