Administrator would like to remove unnecessary data from the state store database.  
Administrator sees that bulk publishing will fail, be partially fail, be slow to complete, or trigger high memory consumption on CD server.

It's possible to cleanup the State Store database by using new functionality, which will periodically clean the database as stated in our documentation here.

• For SDL Web 8.5 the CD_8.5.0.14838 hotfix needs to be applied.
• For Tridion Sites 9 the CD_11.0.0.14838 hotfix needs to be applied.  See KB article for instructions on how to download hotfix.
  Where can I find hotfixes for SDL Tridion Sites/Web?
• This is already included in the Tridion Sites 9.1 release. 

Only the Deployer application.properties file needs to be configured, no task scheduler or O/S cron job is needed.

Also, the administrator may not see that the records are added to the state store tables if testing.  It only happens occasionally when doing high-volume publishing.  As the records accumulate, then the administrator will eventually see high memory utilization and/or publishing failures.  To verify if the hotfix is configured successfully, it should be sufficient to check  the state store tables occasionally and see if the high memory symptoms are occurring again. If they are and there is another buildup of rows in the state store tables, then the hotfix is not working as expected and the administrator should submit a support ticket.

The hotfix will remove unneeded data from these state store tables, and is the equivalent of running these SQL commands manually.  Can run queries against the tables first to see what the current volume of records are.

delete from EXECUTION
delete from EXECUTION_PROPERTY
delete from PIPELINE
delete from STEP

- While checking for unneeded records in the State Store tables, it is also helpful to see if publishing trace files should be removed as discussed in KB article SDL Web - How to cleanup files left over by publishing
- It may also be helpful to tune the Publisher and Deployer microservice, as discussed in KB article For Web 8.5, how to tune the Publisher and Deployer?
- For Tridion Sites 9.1+ and later product versions, it is possible to configure a cron job within the Deployer to automate the removal of unneeded records as discussed in documentation link 
https://docs.sdl.com/783502/753349/sdl-tridion-sites-9-1/scheduling-a-periodic-cleanup-of-the-state-store-database

Also see KB article For Tridion Sites 9.0, will having unneeded data in the state store database tables contribute to high memory consumption on the CD servers?
Also see KB article For Web 8.5, bulk publishing fails with error "Command deserialization failed for file"