Backlogging I/O metadata utilizing counters to monitor write acknowledgements and no acknowledgements

摘要

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.