DBMS backup without suspending updates and corresponding recovery using separately stored log and data files

A database management system, that performs a backup without suspending updates and the backup can be restored using a write-ahead logging protocol restart, comprising:

• means for modifying data in the database management system using a write-ahead logging protocol;
• means for restoring consistency between log records and the data during a restart;
• means for storing data on a first set of storage volumes and storing log records on a second set of storage volumes;
• means for freezing a REDO log point in checkpoint information while a backup system lock is taken;
• and
• means for continuing to update the data while the backup system lock is taken, except for suspending actions that change an external file system catalog, and except for suspending writing updates of objects that extend across a storage volume boundary.

A method of operating a database management system comprising the steps of:

• modifying data in the database management system using a write-ahead logging protocol;
• restoring consistency between log records and the data during a restart;
• storing data on a first set of storage volumes and storing log records on a second set of storage volumes;
• freezing a REDO log point in checkpoint information while a backup system lock is taken;
• and
• continuing to update the data while the backup system lock is taken, except for suspending actions that change an external file system catalog, and except for suspending writing updates of objects that extend across a storage volume boundary.

An article of manufacture comprising computer usable media including at least one computer program recorded therein that is capable of causing a computer system to perform a method of operating a database management system comprising the steps of:

• modifying data in the database management system using a write-ahead logging protocol;
• restoring consistency between log records and the data during a restart;
• storing data on a first set of storage volumes and storing log records on a second set of storage volumes;
• freezing a REDO log point in checkpoint information while a backup system lock is taken;
• and
• continuing to update the data while the backup system lock is taken, except for suspending actions that change an external file system catalog, and except for suspending writing updates of objects that extend across a storage volume boundary.