CONSISTENT BOOKMARK

摘要

A request to generate a snapshot of the master file system for replication is received. The master file system is frozen and a freeze callback function is invoked to generate a consistent point in time. The freeze callback function initiates generation of a bookmark event based on a current time. The bookmark event indicates the consistent point in time for generation of the snapshot. The freeze callback function also initiates capturing I/O events intended for the master file system in order and suspending journal flushing to data storage so as to avoid deadlock of the master file system. The freeze callback function is forwarded and used to generate the snapshot by indicating the consistent point in time to start generation of the snapshot.

主权项

1. A computer-implemented method comprising:
receiving a request to generate a snapshot of the master file system for replication; sending an instruction to halt write operations to the master file system; invoking a freeze callback function to generate a consistent point in time, the freeze callback function initiating:
generating a bookmark event based on a current time, wherein the bookmark event indicates the consistent point in time for generation of the snapshot;capturing file input-output (I/O) events intended for the master file system in order; andsuspending journal flushing to data storage, whereby deadlock of the master file system is avoided; and forwarding the freeze callback function, wherein the bookmark event of the freeze callback function is used to generate the snapshot by indicating the consistent point in time to start generation of the snapshot.