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       sadc - System activity data collector.


       /usr/lib/sysstat/sadc  [ -C comment ] [ -S { INT | DISK | SNMP | IPV6 |
       POWER | XDISK | ALL | XALL } ] [ -F ] [ -L ] [ -V ] [ interval [  count
       ] ] [ outfile ]


       The  sadc  command  samples  system  data  a  specified number of times
       (count) at a specified interval  measured  in  seconds  (interval).  It
       writes in binary format to the specified outfile or to standard output.
       If outfile is set to -, then sadc uses  the  standard  system  activity
       daily data file, the /var/log/sysstat/sadd file, where the dd parameter
       indicates the current day.  By  default  sadc  collects  all  the  data
       available  from  the  kernel.  Exceptions are interrupts and disk data,
       for which the relevant options must be explicitly passed to  sadc  (see
       options below).

       When  the  count  parameter  is  not  specified,  sadc  writes its data
       endlessly.  When both interval and count are not specified, and  option
       -C is not used, a dummy record, which is used at system startup to mark
       the time when the counter  restarts  from  0,  will  be  written.   For
       example, one of the system startup script may write the restart mark to
       the daily data file by the command entry:

       /usr/lib/sysstat/sadc -

       The sadc command is intended to  be  used  as  a  backend  to  the  sar

       Note: The sadc command only reports on local activities.


       -C comment
              When   neither   the  interval  nor  the  count  parameters  are
              specified, this option  tells  sadc  to  write  a  dummy  record
              containing  the specified comment string.  This comment can then
              be displayed with option -C of sar.

       -F     The creation of outfile will be  forced.  If  the  file  already
              exists  and  has  a  format  unknown  to  sadc  then  it will be
              truncated. This may be useful for daily data files created by an
              older  version  of sadc and whose format is no longer compatible
              with current one.

       -L     sadc will try to get an exclusive lock  on  the  outfile  before
              writing  to  it  or  truncating  it.  Failure to get the lock is
              fatal, except in the case of trying to write a normal (i.e.  not
              a  dummy  and not a header) record to an existing file, in which
              case sadc will try again at the next interval. Usually, the only
              reason  a  lock would fail would be if another sadc process were
              also writing to the file. This can happen when cron is  used  to
              launch  sadc.   If  the  system is under heavy load, an old sadc
              might still be running when  cron  starts  a  new  one.  Without
              locking,  this  situation  can  result  in  a  corrupted  system
              activity file.

       -S { INT | DISK | SNMP | IPV6 | POWER | XDISK | ALL | XALL }
              Specify which optional activities should be collected  by  sadc.
              Some  activities are optional to prevent data files from growing
              too large.  The INT keyword indicates that sadc  should  collect
              data  for  system  interrupts.   The DISK keyword indicates that
              sadc should collect data for block devices.  The SNMP  and  IPV6
              keywords  indicate  respectively  that  SNMP and IPv6 statistics
              should be collected by sadc.  The POWER keyword  indicates  that
              sadc  should  collect  power  management  statistics.   The  ALL
              keyword is equivalent to specifying all the keywords  above  and
              therefore all previous activities are collected.

              The  XDISK keyword is an extension to the DISK one and indicates
              that  partition  statistics  should  be  collected  by  sadc  in
              addition to disk statistics. This option works only with kernels
              2.6.25 and later.  The XALL keyword is equivalent to  specifying
              all  the  keywords  above  (including  keyword  extensions)  and
              therefore all possible activities are collected.

              Important note: The activities (including optional  ones)  saved
              in an existing data file prevail over those selected with option
              -S.  As a consequence, appending data to an existing  data  file
              will result in option -S being ignored.

       -V     Print version number then exit.


       The sadc command takes into account the following environment variable:

              If this variable exists and its value is UTC then sadc will save
              its  data  in  UTC time.  sadc will also use UTC time instead of
              local time to determine the current daily data file  located  in
              the /var/log/sysstat directory.


       /usr/lib/sysstat/sadc 1 10 /tmp/datafile
              Write  10  records  of one second intervals to the /tmp/datafile
              binary file.

       /usr/lib/sysstat/sadc -C Backup_Start /tmp/datafile
              Insert the comment Backup_Start into the file /tmp/datafile.


       The /proc filesystem must be mounted for the sadc command to work.

       All the statistics are not  necessarily  available,  depending  on  the
       kernel version used.


              Indicate the daily data file, where the dd parameter is a number
              representing the day of the month.

       /proc contains various files with system statistics.


       Sebastien Godard (sysstat <at>


       sar(1), sa1(8), sa2(8), sadf(1), isag(1)