Abstract: In one aspect, a method includes determining a number of data streams to assign to a volume, assigning a fragment file for each data stream, sending fragment files to a backup storage device, synthesizing the fragment files to form an image file for the volume at the backup device, sending new fragment files with changes to the volume to the backup device and synthesizing the new fragment files with the corresponding image file to form a new image file for the volume.

Abstract: In one aspect, a method includes making a first active buffer a passive buffer, generating a second active buffer to receive new I/Os, making a list of locations that need realignment in the passive buffer, flushing open I/Os at a splitter, reading I/Os which need realignment, discarding re-aligned I/Os for overwritten areas and sending the passive buffer to a replica site.

Abstract: In one aspect, a method includes receiving an I/O, incrementing a first counter in an active data structure in a backlog at a splitter after receiving the I/O, storing I/O metadata of the I/O in the active data structure, incrementing a second counter in the active data structure or a passive data structure in the backlog if the I/O was written to a storage array and received by the data protection appliance and incrementing a third counter in the active data structure or the passive data structure if either the I/O was not written to a storage array or not received by the data protection appliance.