Tested Limits for CMC Migration


Minimum Free Memory:4 GiB
Minimum CPU-Cores:2
Maximum Disks (Source + Destination):128
Migration Speed:Limited by Source/Destination disk performance. Observed over 1 GiB/s at a host.


The migration copy process is running at each host. The performance will be limited by the CPU and storage bandwidth of each host.

The consequences of low CPU resource or storage bandwidth is migration speed and host application disk access impact.

For a test system with more than 4 CPU COREs, the disk bandwidth is shared amount the application I/O and migration I/O. iQoS is used to dictate the sharing of the storage bandwidth such that for a Minimal, Moderate, and Aggressive settings, the migration process will consume up to 25%, 50%, or 75% of the available bandwidth. There is a Relentless mode where migration is deemed as absolute priority over host application I/O for situations that warrant such setting. The setting can be changed dynamically during migration. A calendar based scheduler can automatically change the settings for a workday vs holiday/weekend and by the hour of the day.

Updated on: 23/08/2022

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