# sysstat

## NAME



           sysstat - sysstat configuration file.
    


## DESCRIPTION



           This file is read by sa1(8) and sa2(8) shell scripts from the
           sysstat's set of tools.  It consists of a sequence of shell
           variable assignments used to configure sysstat logging.  The
           variables and their meanings are:
    
           **COMPRESSAFTER**
                  Number of days after which daily data files are to be
                  compressed.  The compression program is given in the **ZIP**
                  variable.
    
           **DELAY_RANGE**
                  Tell **sa2** script to wait for a random delay in the indicated
                  range before running.  This delay is expressed in seconds,
                  and is aimed at preventing a massive I/O burst at the same
                  time on VM sharing the same storage area.  A value of 0
                  means that **sa2** script will generate its reports files
                  immediately.
    
           **HISTORY**
                  The number of days during which a daily data file or a
                  report should be kept. Data files or reports older than
                  this number of days will be removed by the sa2(8) shell
                  script.  Data files and reports are normally saved in the
                  /var/log/sa directory, under the name _saDD_ (for data files)
                  or _sarDD_ (for reports), where the _DD_ parameter indicates
                  the current day.
    
                  The number of files actually kept in the /var/log/sa
                  directory may be slightly higher than the **HISTORY** value due
                  to the way the **sa2** script figures out which files are to be
                  removed (see below "How the sa2(8) script applies **HISTORY**
                  value"). Using a value of 28 keeps a whole month's worth of
                  data. If you set **HISTORY** to a value greater than 28 then
                  you should consider using **sadc** 's option **-D** to prevent older
                  data files from being overwritten (see sadc(8) manual
                  page). In this latter case data files are named _saYYYYMMDD_
                  and reports _sarYYYYMMDD_ , where _YYYY_ stands for the current
                  year, _MM_ for the current month and _DD_ for the current day.
    
                  How the sa2(8) script applies **HISTORY** value
    
                  The **sa2** script uses the **find** command with the **-mtime** option
                  to figure out which files are to be removed. The **find**
                  command interprets this value as "N 24 hour periods",
                  ignoring any fractional part. This means that the last
                  modified time of a given _sa[r]DD_ data or report file, using
                  a **HISTORY** of 1, has to have been modified at least two days
                  ago before it will be removed. And for a **HISTORY** of 28 that
                  would mean 29 days ago.
    
                  To figure out how a **HISTORY** of 28 is applied in practice,
                  we need to consider that the **sa2** script that issues the
                  **find** command to remove the old files typically runs just
                  before midnight on a given system, and since the first
                  record from **sadc** can also be written to the previous day's
                  data file (thereby moving its modification time up a bit),
                  the **sa2** script will leave 30 files untouched. So for a
                  setting of 28, and counting the data file of the current
                  day, there will always be 31 files (or 30 files, depending
                  on the number of days in a month) in the /var/log/sa
                  directory during the majority of a given day.  E.g.:
    
                  April 30th: 31 files (Apr 30th-1st, Mar 31th)
                  May 1st: 30 files (May 1st, Apr 30th-2nd)
    
                  Yet we can note the following exceptions (as inspected at
                  Noon of the given day):
    
                  February 28th: 31 files (Feb 28th-1st, Jan 31st, 30th &
                  29th)
                  March 1st: 30 files (Mar 1st, Feb 28th-2nd, Jan 31st &
                  30th)
                  March 2nd: 29 files (Mar 1st & 2nd, Feb 28th-3rd, Jan.
                  31st)
                  March 3rd: 28 files (Mar 1st-3rd, Feb 28th-4th)
                  March 4th - March 28th: 28 files
                  March 29th: 29 files
                  March 30th: 30 files
                  March 31st: 31 files
    
                  (Determining the number of files in March on a leap year is
                  left as an exercise for the reader).
    
                  Things are simpler if you use the _sa[r]YYYYMMDD_ name
                  format.  Apply the same logic as above in this case and you
                  will find that there are always **HISTORY** + 3 files in the
                  _/var/log/sa_ directory during the majority of a given day.
    
           **REPEAT_HEADER**
                  Maximum number of lines after which a header will be
                  inserted in the report generated by **sa2** script. By default
                  there is only a header at the beginning of each report and
                  it is not repeated afterwards.
    
           **REPORTS**
                  Set this variable to **false** to prevent the **sa2** script from
                  generating reports (the _sarDD_ files).
    
           **SA_DIR** Directory where the standard system activity daily data and
                  report files are saved. Its default value is _/var/log/sa_.
    
           **SADC_OPTIONS**
                  Options that should be passed to sadc(8).  With these
                  options (see sadc(8) manual page), you can select some
                  additional data which are going to be saved in daily data
                  files.  These options are used only when a new data file is
                  created. They will be ignored with an already existing one.
    
           **UMASK** The **sa1** and **sa2** scripts generate system activity data and
                  report files in the _/var/log/sa_ directory. By default the
                  files are created with umask 0022 and are therefore
                  readable for all users. Change this variable to restrict
                  the permissions on the files (e.g. use 0027 to adhere to
                  more strict security standards).
    
           **YESTERDAY**
                  By default **sa2** script generates yesterday's summary, since
                  the **cron** job usually runs right after midnight. If you want
                  **sa2** to generate the summary of the same day (for example
                  when cron job runs at 23:53) set this variable to **no**.
    
           **ZIP** Program used to compress data and report files.
    


## FILE



           _/etc/sysconfig/sysstat_
    


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