LogBufMB

Specifies the size of the internal transaction log buffer in megabytes.

For TimesTen Classic, the LogBufMB attribute specifies the size of the internal transaction log buffer for the database.

For TimesTen Scaleout, the LogBufMB attribute specifies the size of the internal transaction log buffer for the element.

The recommendation is to set LogBufMB to a value between 256 MB and 4 GB. If memory space is a concern, start with 256 MB; otherwise, start with 1 GB.

If you change the value of LogBufMB, you also may need to change the value of LogBufParallelism to satisfy the constraint that LogBufMB/LogBufParallelism >= 8.

If you increase the value of LogBufMB, ensure the value of LogFileSize is greater than or equal to the value of LogBufMB (LogFileSize >= LogBufMB).

Required Privilege

Only the instance administrator can change the value of this attribute.

Usage in TimesTen Scaleout and TimesTen Classic

This attribute is supported in both TimesTen Classic and TimesTen Scaleout.

Setting

Set LogBufMB as follows:

Where to set the attribute	How the attribute is represented	Setting
C or Java programs or UNIX and Linux systems odbc.ini file in TimesTen Classic or in the database definition (.dbdef) file in TimesTen Scaleout	LogBufMB	n - Size of log buffer in megabytes. If not set and the database or element exists, TimesTen uses the value stored in the database. If not set and the database or element is being created, TimesTen uses the default value of 64 MB. The maximum value is 65,536 MB (64 GB).
Windows ODBC Data Source Administrator	Not applicable

Examples

The following shows how to see the value of LogBufMB.

Command> CALL ttConfiguration('LogBufMB');
< LogBufMB, 64 >
1 row found.