Quiesce

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Quiesce means to slow down a computer to save power while still being available. The process may include shutting down some services.

The term is also used to describe minimizing the number of running processes on a computer, particularly those that might modify information stored on disk during a backup in order to guarantee a consistent and useable backup.

This is becoming important in many areas of IT backup systems. Symantec's Livestate product now includes a quiesce process, as does VMware's Virtual ESX3 server's VMotion feature.

Symantec supports - Exchange - SQL

Vmware support - IO system

IBM DB2 supports a Quiesce command that is used to indicate a state for which all users have been locked out of a database or an instance (of databases) so that administrative tasks can be performed. See [DB2 Quiesce Command]

IBM DB2 for z/OS and OS/390 has a utility command called QUIESCE, used in order to make it write all data belonging to a certain database (a logical entity in a DB2 subsystem) from the buffers, helping utility programs get DRAIN access on the datasets quickly.

IBM DB2 for z/OS and OS/390 also supports a command SET LOG SUSPEND that technically speaking, stops it from writing to the log, in fact freezing any database activity (except for most queries). This mode is used sometimes for snapshot type backup schemes, thus only lasting for less than a second, ensuring backed up data is in a consistent state. This command is reversed with a SET LOG RESUME command.