Statistics

CRIU generates a set of stats-<type> files that contain statistics about how dump/restore went. These files are in google-protocol-buffers format, just like the images are, and can be viewed using the criu show -f [FILE] command.

Dump/Pre-dump stats

These are in stats-dump file. Fields are:

freezing_time

Time it took criu to freeze the process tree

frozen_time

Time tasks were in frozen state

memdump_time

Time criu spent grabbing required pages out of processes. This time does not include the next time

memwrite_time

Time criu spend transferring memory pages into image files (locally or on page-server)

All the above times are in microseconds.

pages_scanned

The number of pages criu looked at to decide whether or not to dump them

pages_skipped_parent

The number of pages criu skipped due to they were found in parent images (read about memory changes tracking)

pages_written

The total number of pages criu put into image files

Restore stats

forking_time

Time took to fork the tree of processes (with groups and sessions)

restore_time

Total time of restore

pages_compared

Number of pages compared for being COW-ed

pages_skipped_cow

Number of pages, restoration of which was skipped due to COW setup