Maintaining the SQL Server msdb size should be a regular DBA task. The exact tasks to complete , depend on how you use SQL server

 A typical question I receive is:

 “The MSDB database has grown till 10 GB and now I'm experiencing no more space on disk C:.”

Note: There are different situations where you won’t want to delete history. Plan ahead – and only apply these procedures in accordance with system policies

Exceute SP_DELETE_BACKUPHISTORY 

A system stored procedure . Maintains the size of backup and restore history tables.

It takes one argument : @oldest_date

Execute SP_PURGE_JOBHISTORY

A system stored procedure. The option of deleting all job history records  or the history of one job

Execute SP_MAINTPLAN_DELETE_LOG

Clears up the Maintenance Plan History . This undocumented store  procedure is the equivalent of the “Delete” button on the Maintenance GUI

Possible scenarios include:

 1: User wants to delete all logs

2: User wants to delete all logs older than X date

3: User wants to delete all logs for a given plan

4: User wants to delete all logs for a specific subplan

5: User wants to delete all logs for a given plan older than X date

6: User wants to delete all logs for a specific subplan older than X date