Message type: E = Error
Message class:  CNV21500 - Messages for HR conversions basis 
Message number: 035
Message text: Generation subroutine pool full.
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The SAP error message CNV21500035: Generation subroutine pool full typically occurs during the execution of a conversion or migration process, particularly when using the SAP Conversion Tools or during data migration activities. This error indicates that the system has reached the limit of the number of subroutine pools that can be generated in the ABAP runtime environment.
Cause: Subroutine Pool Limit: Each ABAP program can have a limited number of subroutine pools. When the number of generated subroutine pools exceeds this limit, the system throws this error. Large Data Volume: If the data being processed is large or complex, it may lead to the generation of too many subroutine pools. Inefficient Code: Poorly optimized code or logic in the migration program can lead to excessive subroutine pool generation.
Solution: Optimize the Code: Review the ABAP code for the migration or conversion program. Look for opportunities to optimize the logic to reduce the number of subroutine pools
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