Overview of Accounting Parameters

When activated by the system administrator, the process accounting subsystem maintains log files for storing information about system and user processes. These files can become large, reducing available space for other files on the file system where they reside.

If process accounting is running, the system suspends process accounting whenever the available space on the file system where the accounting files reside falls below a certain threshold. The threshold is defined as the signed, arithmetic sum of the acctsuspend kernel parameter value at system boot time and the minfree file system parameter value that was defined during file system creation. (See “How to Determine Value of minfree”.) When process accounting is suspended, the system issues the message:

Accounting suspended

and accounting remains suspended until enough free space becomes available to resume. The resume threshold value is defined by the signed, arithmetic sum of the acctresume kernel parameter and the minfree file system parameter. To prevent suspend-resume conflicts, acctresume must have a value greater than acctsuspend.

When sufficient file system space becomes available and accounting resumes, the system issues the message:

Accounting resumed

For more information about selecting values for acctsuspend and acctresume, see “Specifying a Threshold Value”.

Suspend Accounting Threshold

The suspend accounting threshold can be set to any value from zero to 100 percent of the usable file system size. Any value for acctsuspend which, when added to minfree, produces a zero or negative result, sets the suspend threshold at 0 percent, allowing accounting files to overwrite the entire reserved minimum free space without being suspended.

Resume Accounting Threshold

The resume accounting threshold also can be set to any value from zero to 100 percent of the usable file system size. If the signed, arithmetic sum of the acctresume value at system boot time plus minfree is 100 or greater, accounting cannot resume until the system is rebooted, or a startup command is executed from the keyboard (see acctsh(1M)). In a more practical sense, any value that results in a resume threshold higher than maximum normal free space on the file system will prevent process accounting from resuming.