Sybase Locks Test

This test, executed by an internal agent, tracks the statistics pertaining to the lock and deadlock traffic of Sybase Adaptive Server. Locking affects the performance of the Sybase adaptive server by limiting the concurrency. An increase in the number of simultaneous users to a server may increase the lock contention thereby decreasing the performance of the server (as one process may have to wait for another process to release its lock, thereby affecting the response time and throughput). Deadlocks cause more severe damage. A deadlock causes one transaction to be aborted and transaction must be restarted by the application. If a deadlock occurs very often, it severely affects the throughput of the application.

Target of the test : A Sybase ASE (Below v15) server

Agent deploying the test : An internal agent

Outputs of the test : One set of results for every Sybase server being monitored.

Configurable parameters for the test
Parameter Description

Test Period

How often should the test be executed.

Host

Refers to the IP address of the Sybase server.

Port

The port number at which the Sybase server listens to.

User

A Sybase user who has the “sa_role”.

Password

The password corresponding to the above user.

Confirm Password

Confirm the password by retyping it here.

Detailed Diagnosis

To make diagnosis more efficient and accurate, the eG Enterprise suite embeds an optional detailed diagnostic capability. With this capability, the eG agents can be configured to run detailed, more elaborate tests as and when specific problems are detected. To enable the detailed diagnosis capability of this test for a particular server, choose the On option. To disable the capability, click on the Off option.

The option to selectively enable/disable the detailed diagnosis capability will be available only if the following conditions are fulfilled:

  • The eG manager license should allow the detailed diagnosis capability
  • Both the normal and abnormal frequencies configured for the detailed diagnosis measures should not be 0.
Measurements made by the test
Measurement Description Measurement Unit Interpretation

Lock requests

The average number of lock requests per second

Locks/sec

A high value indicates that there is high locking activity in the system and may need close scrutiny for the type of locks being requested. The detailed diagnosis for this measure provides a listing of locks requests for each lock type.

Lock waits

The average number of times there was lock contention

Waits/sec

A high value of waits can have an adverse impact on application performance. Possible reasons for this behavior could be:

  • Inadequate number of locks available in the database
  • Unusually high locking behavior of applications accessing the database
  • Improper database application design, etc.

The detailed diagnosis for this measure provides a listing of waited number of locks for each lock type.

Avg lock wait time

The average amount of wait time for each lock request that resulted in a wait

Secs

A high value may indicate that there is contention for locks in the system. When the average wait time for locks is high, users may have to wait for their transactions to complete.

Lock timeouts

The number of times a task was waiting for a lock and the transaction was rolled back due to a session-level or server-level lock timeout

Timeouts/Sec

Lock timeouts can be useful for removing tasks that acquire some locks, and then wait for long periods of time blocking other users. The detailed diagnosis for this measure provides a listing of lock timeouts for each lock type.

Deadlocks

The average number of deadlocks found in the lock requests

Number

A deadlock may arise due to various situations including bad design of queries and deficient coding practices. A deadlock is a situation where both/all the lock requestors are in a mutual or a multi-way tie. Any deadlocks are detrimental to database application performance. The detailed diagnosis for this measure provides a listing of number of dead locks for each lock type.