Modify minor compaction settings

This topic describes the minor compaction parameters and how to set these parameters.

Minor compaction parameters

The most common parameter for controlling minor compactions is major_compact_trigger, which determines the number of minor compactions that triggers a major compaction. If the parameter is set to 0, minor compactions are disabled, and each time the MemTable memory usage of the tenant reaches the specified threshold, a major compaction is directly performed without performing minor compactions. You can configure the parameters based on the specific business needs.

Modify minor compaction parameters by using SQL statements

1. Log on to the database as a tenant administrator.

2. Execute the following statements to modify minor compaction parameters:

   Sample statements:

   obclient> ALTER SYSTEM SET minor_compact_trigger=2;
   
   obclient> ALTER SYSTEM SET major_compact_trigger=10;
   
   obclient> ALTER SYSTEM SET freeze_trigger_percentage=20;
   
   obclient> ALTER SYSTEM SET memstore_limit_percentage=50;
   

3. After the parameters are modified, you can execute the SHOW PARAMETERS statement to check whether the modification is successful.

   Sample statements:

    obclient> SHOW PARAMETERS LIKE 'minor_compact_trigger';
   
   obclient> SHOW PARAMETERS LIKE 'major_compact_trigger';
   
   obclient> SHOW PARAMETERS LIKE 'freeze_trigger_percentage';
   
   obclient> SHOW PARAMETERS LIKE 'memstore_limit_percentage';