Measures reported by UnivDBSessTest

Administrators can limit the number of sessions that can be established on a UniVerse database server, so as not to choke the server. At frequent intervals, administrators should monitor the session count on the server and figure out if the maximum session limit is about to be reached or not. This will enable administrators to proactively detect potential overload conditions, and take pre-emptive action against the same. This is exactly what the UnivDBSessTest test helps administrators achieve!

At configured intervals, this test reports the session load and overall session usage by the users of the database server, and warns administrators of a probable overload condition on the server. Additionally, the test also reports the number and type of sessions launched per user, and thus reveals which user(s) has contributed the most to the overload and the type of sessions responsible for the same. The details of users and their sessions are also revealed as part of detailed diagnostics. Using these useful problem pointers, administrators can decide between killing idle sessions to reduce the load on the server or increasing the session limit to accommodate more number of sessions.

Output of the test : One set of results for every user who is currently logged into the database server. Measures will also be reported for an additional All descriptor. The session load and usage metrics will be aggregated across all users and reported for this descriptor.

The measures made by this test are as follows:

Measurement	Description	Measurement Unit	Interpretation
noOfMaxConfiguredUse	Indicates the maximum number of sessions that can be launched on the target UniVerse database server.	Number	This measure will only be reported for the ‘All’ descriptor of this test.
totalSessions	Indicates the total number of sessions currently opened by this user. For the All descriptor, this measure will report the total number of open sessions on the target UniVerse database server, regardless of user.	Number	Using the value that this measure reports for the All descriptor, you can gauge how loaded the server is presently. You can then compare the value of this measure with the value of the noOfMaxConfiguredUse measure to know if the server is fast approaching its session limit or can accommodate many more sessions. If the former is true, it indicates a potential overload condition on the server. You can then compare the value of this measure across users to know which user is contributing the most to the overload.
sessionUsage	Indicates the percentage of sessions utilized by this user. For the All descriptor, this measure will report what percentage of the maximum session limit is being used by all users logged into the server.	Number	A value close to 100% for the All descriptor reveals that too many sessions are currently open on the server, and may soon cause the server to consume its session limit. If that happens, then the server will deny access to new session requests. To avoid this, first check whether the server is sized with adequate resources to handle additional load, and if so, increase the session limit of the server. However, if the server does not have enough processing power, then you may want to kill the sessions that are idle or are engaged in inconsequential operations, so that the load on the server drops; this way, you can make room for newer sessions as well. To achieve this, first compare the value of this measure across users to know which user is contributing to the overload. Then, use the detailed diagnosis of the interactiveSessions and backgroundSessions measures of that user to know which sessions of these users are unnecessarily consuming resources, and target such sessions for termination.
interactiveSessions	Indicates the total number of interactive processes initiated by this user. For the All descriptor, this measure will report the sum total of interactive processes initiated by all users of the database server.	Number	Interactive processes are those that are initiated by the user and run in the foreground. Background processes are those that are initiated by the user using the PHANTOM command. Phantom processes run in the background and are useful for long running or load spreading operations. If the value of the Session usage measure is close to 100% for the All descriptor, then compare the value of the interactiveSessions and backgroundSessions measure for that descriptor to know what type of sessions are causing the overload. If interactive sessions are contributing to the overload, then compare the value of the Interactive sessions measure across users to know which user has initiated the maximum number of interactive processes. Then, use the detailed diagnosis of the Interactive sessions measure of that user to view the PID of the interactive processes, the command that was last executed by each process, which terminal that user logged in from, and what time the user logged in. From this, you can identify the interactive sessions that have been open for too long a time running inconsequential commands, and mark them for termination. Likewise, if background sessions are contributing to the overload, then compare the value of the backgroundSessions measure across users to know which user has initiated the maximum number of background processes. Then, use the detailed diagnosis of the Background sessions measure of that user to view the PID of the background processes, the command that was last executed by each process, which terminal that user logged in from, and what time the user logged in. From this, you can identify the background sessions that have been open for too long a time running inconsequential commands, and mark them for termination.
backgroundSessions	Indicates the number of background processes initiated by this user. For the All descriptor, this measure will report the sum total of all background processes initiated by all users of the database server.	Number