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.TH SADC 8 "JUNE 2006" Linux "Linux User's Manual" -*- nroff -*-
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sadc \- System activity data collector.
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.B /usr/lib/sa/sadc [ -d ] [ -F ] [ -I ] [ -L ] [ -V ] [
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command samples system data a specified number of times (
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) at a specified interval measured in seconds (
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). It writes in binary format to the specified
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or to the standard output. If
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uses the standard system activity daily data file, the
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file, where the dd parameter indicates the current day.
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collects all the data available from the kernel.
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Exceptions are interrupts and disks data, for which the
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relevant options must be explicitly passed to
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parameter is not specified,
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writes its data endlessly.
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are not specified, a dummy record, which is used at system startup to mark
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the time when the counter restarts from 0, will be written.
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For example, one of the system startup script may write the restart mark to
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the daily data file by the command entry:
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.B "/usr/lib/sa/sadc -"
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command is intended to be used as a backend to the
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command only reports on local activities.
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to report statistics for disks. By default
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does not report disks activity to prevent data files from growing too large.
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will be forced. If the file already exists and has not the format expected by
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then it will be truncated. This may be particularly useful for daily data files
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created by an older version of sadc and whose format is no longer compatible
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to report statistics for all system interrupts. By default
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only reports statistics for the total number of interrupts.
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will try to get an exclusive lock on the
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before writing to it or truncating it. Failure to get the lock is fatal,
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except in the case of trying to write a normal (i.e. not a dummy and not
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a header) record to an existing file, in which case
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will try again at the next interval. Usually, the only reason a lock
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would fail would be if another
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process were also writing to the file. This can happen when cron is used
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If the system is under heavy load, an old
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might still be running when cron starts a new one. Without locking,
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this situation can result in a corrupted system activity file.
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Print version number then exit.
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command takes into account the following environment variable:
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If this variable exists and its value is
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will save its data in UTC time.
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will also use UTC time instead of local time to determine the current
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daily data file located in the
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.B /usr/lib/sa/sadc 1 10 /tmp/datafile
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Write 10 records of one second intervals to the /tmp/datafile binary file.
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filesystem must be mounted for the
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All the statistics are not necessarily available, depending on the kernel version used.
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.IR /var/log/sa/sa dd
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Indicate the daily data file, where the
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parameter is a number representing the day of the month.
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contains various files with system statistics.
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Sebastien Godard (sysstat <at> wanadoo.fr)
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.I http://perso.orange.fr/sebastien.godard/
added
removed
man/sadc.8
