Blob image copy considerations

MMT uses several parallel sub-routines in copying image blobs, the number of which is controlled by the --parallel-io-count parameter, which has a default value of 4.

Image blobs are copied only when you are using the copy storage mode for your migration, during the Extract and Restore stages of the migration workflow. For optimum performance, the number of CPU resources to allocate for the MMT container (--cpus=<value>) is --parallel-io-count, plus one for MMT itself.