Additional Memory Requirements

The amount of RAM needed for the AhsayCBS server to run efficiently depends on:

  • The memory required for the operating system to run efficiently.
  • The type of backup jobs; agent based backup where the backup is processed on the customer machine or an agentless (Run on Server) backup job such as Microsoft 365 or Cloud File backup where the backup job is processed by the AhsayCBS server itself.

    • Agent based backup

      As the agent based backup rely on AhsayOBM/AhsayACB backup client to process the backup, the Java heap size required is relatively small. For most AhsayCBS servers a setting of 4096M or 4GB of Java heap size is sufficient. The default Java heap size is 2048 or 2GB.

      For example, the AhsayCBS server will require a minimum of 8GB of RAM, 4GB (for the Operating System) + 4GB (for AhsayCBS service) = 8GB of RAM.

      For an AhsayCBS server hosting agent based backups, the Java heap size should not exceed 2/3 of RAM available to allow sufficient resources for the operating system.

    • Agentless backup

      Although the backup job is processed by the AhsayCBS server itself with each backup job having its own separate Java process and Java heap size, it is still recommended that the AhsayCBS service should have a Java heap size of 4096M or 4GB. As restore, data integrity check and space freeing up feature for agentless Microsoft 365 and Cloud File backup sets will still utilize Java memory from the AhsayCBS service.

      For example, if the AhsayCBS server is hosting 20 agentless (Run on Server) Microsoft 365 backup jobs, each backup job has a default Java heap size of 2048M or 2GB of memory. The AhsayCBS server will require 48GB of RAM. That is 40GB (for the 20 Microsoft 365 backup jobs) + 4GB (for the Operating System) + 4GB (for AhsayCBS service) = 48GB of RAM.

      Although based on the estimated 48GB RAM usage, a server with 64GB RAM is sufficient. For an on-premises server, it is recommended to provision additional RAM to meet unexpected on-going requirements and future business growth.

Review usage regularly, if more backup sets are created then more RAM may need to be added. If there is not enough RAM to accommodate all agentless Microsoft 365 & Cloud File backup jobs running concurrently, then some backup jobs will not run.
AhsayCBS (DIY)