Changes

== Changes tracking ==

== Changes tracking ==

For [[iterative migration]] it's very useful to track changes in memory. Until 2.5 changes were tracked for anonymous memory only, but now criu does this for shared memory as well. To do it criu scans all the shmem segment owners' pagemap (as it does for anon memory) and then AND-s the collected soft-dirty bits.

For [[iterative migration]] it's very useful to track changes in memory. Until CRIU v2.5, changes were tracked for anonymous memory only, but now it is also shared memory can be tracked as well. To achieve it, CRIU scans all the shmem segment owners' pagemap (as it does for anonymous memory) and then ANDs the collected soft-dirty bits.

The changes tracking made developers implement [[Memory images deduplication]] for shmem segments as well.

The changes tracking caused developers to implement [[memory images deduplication]] for shmem segments as well.

== Dumping present pages ==

== Dumping present pages ==