Fast Initialization of file system snapshot
Original Publication Date: 2003-Nov-20
Included in the Prior Art Database: 2003-Nov-20
A program is disclosed that minimizes the amount of time needed to create a file system snapshot. A file system snapshot establishes a consistent block level image of the file system at a point-in-time. A snapshot is used for creating backups of an active file system. When a file system snapshot is created, the file system must block all writes to the file system during the initialization of the snapshot. The main part of snapshot initialization involves synchronous initialization of a data structure that is proportional to the size of the file system. This takes too much time for modern large file systems. The problem solved is to minimize the amount of time needed to create the snapshot.