ArticlesPSA: Error Message: "System.LimitException: Apex heap size too large: 21043845" when Running Backlog Calculation

When Running Backlog Calculation.Error Message: "System.LimitException: Apex heap size too large: 21043845" 

• Professional Services Automation
• All Versions

Apply the below solutions :

• Change the BackLog Custom Settings:
  1. Go to Setup > Develop > Custom Settings
  2. Click Manage next to the label Backlog 
  3. Click Edit
     1. Lower following batch sizes to "5"
        1. Post Process Milestone Batch Size
        2. Post Process RPG Batch Size
        3. Post Process Project Batch Size 
        4.  Post Process Resource Request Batch Size
           
     2. Lower Assignment Batch Size to "20"  to  "5"
     3. Uncheck Process Backlog Remainder Inline
     4. Click Save

1. Check Perpetual Time Period does not goes out to more than 10 years. 
   
2. Weekly Time Periods does not go out to more than 10 years. 
3. Check Milestone target date does not go out to more than 10 years.  4.
4. Check if single project has very large numbers of Assignments or Milestones

   1. Can try excluding such Projects from the backlog by checking 'Exclude from Backlog' on project.

   2. Also exclude any templates or other Projects not necessary to calculate Backlog for.
      
      
      

• Error is caused by Backlog  trying to calculate large amounts of data, usually starting at the Global Region, Practice and/or Group
• When there is no End Date on the Backlog Calculation, calculation tries to calculate all backlogs up to the last day of the Perpetual Time Period
  • For example, if the Time Period record with "Perpetual" Time Period Type ends on 12/31/2050, the Backlog Calculation will calculate up to that date
• The Backlog Custom Settings batch sizes are set to high

You might see this error Error Message: "First error: pse: Too many DML rows: 10001" when Running Backlog Calculation along with above.