Postponed backout in a data sharing environment
Two options on the DSNTIPL1 installation panel allow you to enable and control postponed backout.
You can postpone backout processing for in-abort and inflight units of recovery (URs). The advantage of postponing backout processing is that Db2 can be up and accepting new work before handling backout processing.
- LIMIT BACKOUT
The AUTO, YES, LIGHT, and LIGHTAUTO values of the LIMIT BACKOUT field enable postponed backout. AUTO and LIGHTAUTO are the recommended values because you do not have to remember to issue commands to start backout processing. The AUTO and LIGHTAUTO values result in the same behavior for normal Db2 restart. However, the LIMIT BACKOUT field is ignored when AUTO is specified during Db2 restart with the LIGHT(YES) or LIGHT(NOINDOUBTS) option.
- BACKOUT DURATION
A multiplier that is used to calculate how much log processing to back out during restart. This option is valid only when AUTO, YES, LIGHT, or LIGHTAUTO is specified for the LIMIT BACKOUT field.