Garbage Collection Analysis attributes

The attributes provide garbage collection analysis information.

The Garbage Collection Analysis attribute group provides information about the garbage collector in the Java™ virtual machine (JVM) that is hosting the application server.

The garbage collection attributes report the number of times the collector ran during the interval and the resulting number of objects that the collector freed. Use the Garbage Collection Analysis attributes in situations to monitor garbage-collection performance and possible problems. The attributes within this group are used to build the Garbage Collection Analysis and the WebSphere® Application Server workspaces.

ASID The identifier (decimal) assigned to the address space running this servant region.

GC Rate (per min) The rate (per minute) at which the JVM is invoking its garbage-collection routine. The valid format is a decimal (formatted to 3 decimal places).

Heap Used (%) The percentage of heap used at the end of the interval. The valid format is a decimal (formatted to 1 decimal places).

Interval (sec) The length (in seconds) of the sampling interval. The valid format is a positive integer.

Kbytes Free The total number of free kilobytes in the heap at the end of the last garbage-collection cycle during the interval. The valid format is a positive integer.

Kbytes Total Freed by GC The total number of kilobytes freed by the garbage collector during the interval. The valid format is a positive integer.

Kbytes Used The number of kilobytes in the heap that were in use at the end of the last garbage collection cycle during the interval. The valid format is a positive integer.

Kbytes Used Delta The difference between the Kbytes Used value for this interval and the Kbytes Used value for the prior interval. The valid format is a positive or negative integer.

Node Name The name of the system on which the server is running. The valid format is an alphanumeric string, with a maximum of 256 characters.

Objects Freed The number of objects the garbage collector freed during the interval (only supported for IBM® JDK). The valid format is a positive integer. Not monitored on non-IBM JVMs, including those commonly used on HP-UX and Solaris platforms.

Objects Moved The number of objects the garbage collector moved during the interval (only supported for IBM JDK). The valid format is a positive integer. Not monitored on non-IBM JVMs, including those commonly used on HP-UX and Solaris platforms.

Origin Node The name of the server subnode. The valid format is an alphanumeric string, with a maximum of 128 characters.

Process ID The unique identifier of the JVM process (the class ID of the JVM). The valid format is a positive integer.

Real Time (ms) The total real time (in milliseconds) the garbage collector required during the most recent cycle. The valid format is a positive integer.

Real Time (%) The percentage of real time that the garbage collector was active during the interval. The valid format is a decimal (formatted to 1 decimal place).

Sample Date and Time The date and time the monitoring agent collected the data. The valid format is a 12-character timestamp. For the STR and SCAN functions, the format is MM/DD/YY HH:MM:SS; the following table shows the values contained in this character string:

Example: 09/13/06 18:32:03 indicates the data was collected on September 13, 2006, at 18:32:03.

This attribute was designed for logging and reporting data-collection times rather than for creating situations. To specify a time and date for comparison and testing, use attributes from the Universal Time or Local Time groups.

Server Name The name of the WebSphere Application Server. The valid format is an alphanumeric string, with a maximum of 256 characters.

Summary Indicates that this row is a summary row of statistical totals for all rows.

Times Run The number of times the garbage collector ran during the interval. The valid format is a positive integer.