NAME¶
db4.8_checkpoint - Periodically checkpoint transactions
SYNOPSIS¶
db4.8_checkpoint [-1Vv] [-h home] [-k kbytes] [-L file] [-P password] [-p
min]
DESCRIPTION¶
The db4.8_checkpoint utility is a daemon process that monitors the database log,
and periodically calls DB_ENV->txn_checkpoint to checkpoint it.
OPTIONS¶
- -1
- Checkpoint the log once, regardless of whether or not there
has been activity since the last checkpoint and then exit.
- -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 every
kbytes of log file are written.
- -L
- Log the execution of the db4.8_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 the db4.8_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 every min 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.
The db4.8_checkpoint utility uses a Berkeley DB environment (as described for
the
-h option, the environment variable
DB_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,
db4.8_checkpoint should always be given the chance to detach from the
environment and exit gracefully. To cause db4.8_checkpoint to release all
environment resources and exit cleanly, send it an interrupt signal (SIGINT).
The db4.8_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, the
db4.8_checkpoint utility should be started.
The DB_ENV->txn_checkpoint method is the underlying method used by the
db4.8_checkpoint utility. See the db_checkpoint utility source code for an
example of using DB_ENV->txn_checkpoint in a IEEE/ANSI Std 1003.1 (POSIX)
environment.
The db4.8_checkpoint utility exits 0 on success, and >0 if an error occurs.
ENVIRONMENT¶
- DB_HOME
- 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 DB_ENV->open.
AUTHORS¶
Sleepycat Software, Inc. This manual page was created based on the HTML
documentation for db_checkpoint from Sleepycat, by Thijs Kinkhorst
<thijs@kinkhorst.com>, for the Debian system (but may be used by
others).