IBM Tivoli Composite Application Manager for Application Diagnostics, Version 7.1.0.1

Servlet Sessions attributes

The Servlet Sessions attribute group provides information about servlet sessions.

A session is a series of requests to a servlet, originating from the same user at the same browser. Applications running in a Web container use Sessions to monitor the actions of individual users. The attributes within this group are used to build the Sessions workspace.

For information about WebSphere PMI metrics, see WebSphere PMI Attribute Mapping.

Average Concurrently Active Sessions

The average number of concurrently active sessions during the sampling interval. A session is active if WAS is currently processing a request that uses the session. Format is decimal (formatted to 3 decimal places). This value is an average of several values collected over an interval. The interval can be either between this time and the previous time you activated this workspace, or fixed (normally 60 seconds), depending on the configuration of the monitoring agent.

Average Concurrently Live Sessions

The average number of sessions cached in memory during the sampling interval. Format is decimal (formatted to 3 decimal places). This value is an average of several values collected over an interval. The interval can be either between this time and the previous time you activated this workspace, or fixed (normally 60 seconds), depending on the configuration of the monitoring agent.

Average Serializable Session Object Size (bytes)

The average size (in bytes) of the serializable attributes of in-memory sessions. This number is at a session level only and includes only session objects that contain at least one serializable attribute object (a session can contain some attributes that are serializable and some that are not). This value is a measurement of the data at the end of the PMI

sampling interval, not of the data in the entire sampling interval. Format is positive integer.

Average Session Lifetime (ms)

The average session lifetime (in milliseconds), calculated by subtracting the time the session was created from the time it was invalidated. Format is decimal (formatted to 3 decimal places).

Broken Session Affinities

The number of HTTP session affinities that broke, not counting WAS intentional breaks of session affinity. This is the number of requests received for sessions that were last accessed from another Web application and can indicate failover processing or a corrupted plug-in configuration. Format is positive integer.

Broken Session Affinity Rate (per sec)

The rate (per second) of the number of HTTP session affinities that break, not counting the WAS intentional breaks of session affinity, during the sampling interval. Format is decimal (formatted to 3 decimal places).

Cache Discard Rate

(per sec)

The rate (per second) at which session objects have been forced out of the cache during the sampling interval. Format is decimal (formatted to 3 decimal places).

Cache Discards

The number of session objects that have been forced out of the cache. An LRU algorithm removes old entries to make room for new sessions and cache misses (this applies only to persistent sessions). Format is positive integer.

Enterprise Application Name

The name of the Enterprise application running the servlet. Alphanumeric string.

External Read Size (bytes)

The size (in bytes) of the session data read from the persistent store (applicable only to serialized, persistent sessions). Format is decimal (formatted to 3 decimal places).

External Read Time (ms)

The time (in milliseconds) taken to read the session data from the persistent store (applicable only to persistent sessions). For multirow sessions, the metrics are for the attributes; for single-row sessions, the metrics are for the whole session. When using a JMS persistent store, the user has the choice of whether to serialize the data being replicated; if the data are not serialized, this counter is not available. Format is decimal (formatted to 3 decimal places).

External Write Size (bytes)

The size (in bytes) of session data written to the persistent store (applicable only to serialized, persistent sessions). Format is decimal (formatted to 3 decimal places).

External Write Time (ms)

The time (in milliseconds) taken to write the session data from the persistent store (applicable only to serialized, persistent sessions). Format is decimal (formatted to 3 decimal places).

Failed Session Request Rate

(per sec)

The rate (per second) that a request for a new session could not be handled because it would exceed the maximum session count for the sampling interval. Format is decimal (formatted to 3 decimal places).

Failed Session Requests

This attribute collects data from the NoRoomForNewSessionCount metric in the Servlet Sessions Counters PMI

module. The number of times a request for a new session could not be handled because it would exceed the maximum session count; this applies only to a session in memory with AllowOverflow=false. Format is positive integer.

Instrumentation Level

The Web instrumentation level for this Web application. For WebSphere 5, the valid values are None, Low, Medium, High, and Maximum; for WebSphere 6 or higher, the valid values are None, Basic, Extended, All, Custom. Blank if no instrumentation level is set.

Interval (sec)

The length (in seconds) of the sampling interval. Format is positive integer.

Max Serializable Session Object Size (bytes)

The maximum size (in bytes) of the serializable attributes of in-memory sessions. This number is at a session level only and includes only session objects that contain at least one serializable attribute object (a session can contain some attributes that are serializable and some that are not). This value is a measurement of the data at the end of the PMI

sampling interval, not of the data in the entire sampling interval. Format is positive integer.

Min Serializable Session Object Size (bytes)

The minimum size (in bytes) of the serializable attributes of in-memory sessions. This number is at a session level and includes only session objects that contain at least one serializable attribute object (a session can contain some attributes that are serializable and some that are not). This value is a measurement of the data at the end of the PMI

sampling interval, not of the data in the entire sampling interval. Format is positive integer.

Node Name

The name of the system on which the server is running. Alphanumeric string.

Nonexistent Session Request Rate

(per sec)

The rate (per second) of requests for a session that no longer exists (presumably because the session timed out) during the sampling interval. Format is decimal (formatted to 3 decimal places).

Nonexistent Session Requests

The number of requests for a session that no longer exists (presumably because the session timed out). Use this counter to determine if the timeout is too short. Format is positive integer.

Origin Node

The name of the server subnode. Alphanumeric string. Maximum 128 characters.

Sample Date and Time

The date and time the Tivoli Enterprise Management 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:


Format of the 12-character timestamp

Character String Meaning
MM Month
DD Day
YY Year
HH Hour
MM Minute
SS Second

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 WAS. Alphanumeric string.

Session Creation Rate

(per sec)

The rate (per second) of sessions created during the sampling interval. Format is decimal (formatted to 3 decimal places).

Session Invalidation Rate (per sec)

The rate (per second) at which sessions were invalidated during the sampling interval. Format is decimal (formatted to 3 decimal places).

Sessions Created

The number of sessions created during the sampling interval. Format is positive integer.

Sessions Invalidated

The number of sessions invalidated during the sampling interval. Format is positive integer.

Set Instrumentation Level

Type

Indicates the WebSphere resource category, which is used by the agent to modify the Instrumentation Level for transaction data collection.

Summary of Servlet Sessions

Whether this row is a summary row of statistical totals collected for the servlet sessions. The valid values are No and Yes.

Time since Last Activated

The time difference (in the locale-specific format, for example hh:mm:ss.msecs) between the previous and current access timestamps. Does not include session timeouts. The valid format is a timestamp.

Total Serializable Session Object Size (bytes)

The total size (in bytes) of all the in-memory session objects. This includes only the serializable attributes in the session object; at least one such attribute must be present to be included in this total. This value is a measurement of the data at the end of the PMI

sampling interval, not of the data in the entire sampling interval. Format is positive integer.

Web Application Archive

The name of the Web application WAR file. Alphanumeric string.

Additional information:


Parent topic:

Attributes for ITCAM Agent for WebSphere Applications