Using normalized blocks for incremental backups of large virtual machines

A non-transitory computer readable medium comprising computer readable program code, which when executed by a computer processor enables the computer processor to perform a method, the method comprising:

• obtaining, by a backup agent, a backup request for an incremental backup of a VM;
• in response to the backup request:
• obtaining a resilient change tracking (RCT) data structure associated with the VM;
• sorting a set of tracked changes specified in the RCT based on offset;
• performing a size normalization of the set of tracked changes to obtain a set of normalized blocks;
• storing a normalized blocks metadata table in the backup agent, wherein the normalized blocks metadata table comprises a mapping between the set of tracked changes and the set of normalized blocks;
• and
• initiating storage of the incremental backup in a backup storage system using the normalized blocks metadata table.

A system, comprising:

• a processor;
• and
• memory comprising instructions, which when executed by the processor, perform a method, the method comprising:
• obtaining, by a backup agent, a backup request for an incremental backup of a VM;
• in response to the backup request:
• obtaining a resilient change tracking (RCT) data structure associated with the VM;
• sorting a set of tracked changes specified in the RCT based on offset;
• performing a size normalization of the set of tracked changes to obtain a set of normalized blocks;
• storing a normalized blocks metadata table in the backup agent, wherein the normalized blocks metadata table comprises a mapping between the set of tracked changes and the set of normalized blocks;
• and
• initiating storage of the incremental backup in a backup storage system using the normalized blocks metadata table.