5.2 Optional Configuration for Blocker Resolver

You can adjust the sensitivity, and control the size and number of the log files used by Blocker Resolver.

Note:

The DBMS_HANG_MANAGER package is deprecated in Oracle Database 23ai. Use DBMS_BLOCKER_RESOLVER instead. The DBMS_HANG_MANAGER package provides a method of changing some configuration parameters and constraints to address session issues. This package is being replaced with DBMS_BLOCKER_RESOLVER. DBMS_HANG_MANAGER can be removed in a future release.

Sensitivity

If Blocker Resolver detects a delay, then Blocker Resolver waits for a certain threshold time period to ensure that the sessions are delayed. Change threshold time period by using DBMS_BLOCKER_RESOLVER to set the sensitivity parameter to either Normal or High. If the sensitivity parameter is set to Normal, then Blocker Resolver waits for the default time period. However, if the sensitivity is set to High, then the time period is reduced by 50%.

By default, the sensitivity parameter is set to Normal. To set Blocker Resolver sensitivity, run the following commands in SQL*Plus as SYS user:

  • To set the sensitivity parameter to Normal:
    exec dbms_blocker_resolver.set(dbms_blocker_resolver.sensitivity, dbms_blocker_resolver.sensitivity_normal);
  • To set the sensitivity parameter to High:
    exec dbms_blocker_resolver.set(dbms_blocker_resolver.sensitivity, dbms_blocker_resolver.sensitivity_high);

Size of the Trace Log File

The Blocker Resolver logs detailed diagnostics of the delays in the trace files with _base_ in the file name. Change the size of the trace files in bytes with the base_file_size_limit parameter. Run the following command in SQL*Plus, for example, to set the trace file size limit to 100 MB:
exec dbms_blocker_resolver.set(dbms_blocker_resolver.base_file_size_limit, 104857600);

Number of Trace Log Files

The base Blocker Resolver trace files are part of a trace file set. Change the number of trace files in trace file set with the base_file_set_count  parameter. Run the following command in SQL*Plus, for example, to set the number of trace files in trace file set to 6:
exec dbms_blocker_resolver.set(dbms_blocker_resolver.base_file_set_count,6);

By default, base_file_set_count parameter is set to 5.

Parent topic: Resolving Database and Database Instance Delays