db_checkpoint [-1Vv] [-h home] [-k kbytes] [-L file] [-P password] [-p min]
Thedb_checkpoint utility is a daemon process that monitors the database log, and periodically callsDB_ENV->txn_checkpoint() to checkpoint it.
The options are as follows:
-1
Force a single checkpoint of the log (regardless of whether or not there has been activity since the last checkpoint), and then exit.
When the-1 flag is specified, thedb_checkpoint utility will checkpoint the log even if unable to find an existing database environment. This functionality is useful when upgrading database environments from one version of Berkeley DB to another.
-h
Specify a home directory for the database environment; by default, the current working directory is used.
-k
Checkpoint the database at least as often as everykbytes of log file are written.
-L
Log the execution of thedb_checkpoint utility to the specified file in the following format, where### is the process ID, and the date is the time the utility was started.
db_checkpoint: ### Wed Jun 15 01:23:45 EDT 1995
This file will be removed if thedb_checkpoint utility exits gracefully.
-P
Specify an environment password. Although Berkeley DB utilities overwrite password strings as soon as possible, be aware there may be a window of vulnerability on systems where unprivileged users can see command-line arguments or where utilities are not able to overwrite the memory containing the command-line arguments.
-p
Checkpoint the database at least everymin minutes if there has been any activity since the last checkpoint.
-V
Write the library version number to the standard output, and exit.
-v
Write the time of each checkpoint attempt to the standard output.
At least one of the-1,-k, and-p options must be specified.
Thedb_checkpoint utility uses a Berkeley DB environment (as described for the-h option, the environment variableDB_HOME, or because the utility was run in a directory containing a Berkeley DB environment). In order to avoid environment corruption when using a Berkeley DB environment,db_checkpoint should always be given the chance to detach from the environment and exit gracefully. To causedb_checkpoint to release all environment resources and exit cleanly, send it an interrupt signal (SIGINT).
Thedb_checkpoint utility does not attempt to create the Berkeley DB shared memory regions if they do not already exist. The application that creates the region should be started first, and once the region is created, thedb_checkpoint utility should be started.
TheDB_ENV->txn_checkpoint() method is the underlying method used by thedb_checkpoint utility. See thedb_checkpoint utility source code for an example of usingDB_ENV->txn_checkpoint() in a IEEE/ANSI Std 1003.1 (POSIX) environment.
Thedb_checkpoint utility exits 0 on success, and >0 if an error occurs.
If the-h option is not specified and the environment variable DB_HOME is set, it is used as the path of the database home, as described in theDB_ENV->open() method.