Sybase Transaction Log Test

This test reports statistics pertaining to the transaction logs of a Sybase database server.

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

ULC log writes

The rate at which log records per transaction are written into the ULCs

Records/Sec

If this data is unusual, study the Max ULC size measure and look at your application for long-running transactions and for transactions that modify a large number of rows.

Waits for ULC log writes

The rate at which attempts made to write to ULCs encountered semaphore contention

Waits/Sec

 

ULC flushes

The rate at which user log caches (ULCs) were flushed to a transaction log

Flushes/Sec

The detailed diagnosis for this measure provides the percentage of ULC flushes due to full ULC, end transaction, change of database, system log record and other reasons.

Waits for ULC flushes

The rate at which attempts made to flush ULC pages to the log encountered log semaphore contention

Waits/Sec

If this value is high, reduce the semaphore contention by:

  • Increasing the ULC size, if filling user log caches is a frequent cause of user log cache flushes
  • Reducing log activity through transaction redesign. Aim for more batching with less frequent commits. Be sure to monitor lock contention as part of the transaction redesign.
  • Reducing the number of multidatabase transactions, since each change of database context requires a log write.
  • Dividing the database into more than one database so that there are multiple logs. If you choose this solution, divide the database in such a way that multidatabase transactions are minimized.

Max ULC size

The maximum number of bytes used in any ULCs, across all ULCs. This data can help you determine if ULC size is correctly configured.

KB

If this value is consistently less than the defined value for the user log cache size configuration parameter, reduce the user log cache size to Max ULC size value.

Log allocations

The rate at which additional pages were allocated to the transaction log

Allocations/Sec

This data is useful for comparing to other data in this test and for tracking the rate of transaction log growth.

Transaction log writes

The rate at which the Adaptive server wrote a transaction log page to disk

Pages/Sec

 

Avg writes per log page

The average number of times each log page was written to disk

Writes/Page

In high throughput applications, this number should be as low as possible.