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Top Forums Programming Ways to preserve a memory cache Post 302700055 by jim mcnamara on Wednesday 12th of September 2012 11:17:33 PM
Old 09-13-2012
POSIX message queues persist over crash/reboot, until mq_unlink is called. They can be re-opened in the state they were. They are implemented as files without file semantics.

The only thing that CAN persist over a crash/reboot is a physical object - like bytes on a disk, flash disk, tape, etc.

SYSV and POSIX IPC objects are kernel persistent. They survive a program crash.
Not a system crash or reboot.
 

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Apache::Session::Oracle(3pm)				User Contributed Perl Documentation			      Apache::Session::Oracle(3pm)

NAME
Apache::Session::Oracle - An implementation of Apache::Session SYNOPSIS
use Apache::Session::Oracle; #if you want Apache::Session to open new DB handles: tie %hash, 'Apache::Session::Oracle', $id, { DataSource => 'dbi:Oracle:sessions', UserName => $db_user, Password => $db_pass, Commit => 1 }; #or, if your handles are already opened: tie %hash, 'Apache::Session::Oracle', $id, { Handle => $dbh, Commit => 1 }; DESCRIPTION
This module is an implementation of Apache::Session. It uses the Oracle backing store and no locking. See the example, and the documentation for Apache::Session::Store::Oracle for more details. USAGE
The special Apache::Session argument for this module is Commit. You MUST provide the Commit argument, which instructs this module to either commit the transaction when it is finished, or to simply do nothing. This feature is provided so that this module will not have adverse interactions with your local transaction policy, nor your local database handle caching policy. The argument is mandatory in order to make you think about this problem. This module also respects the LongReadLen argument, which specifies the maximum size of the session object. If not specified, the default maximum is 8 KB. AUTHOR
This module was written by Jeffrey William Baker <jwbaker@acm.org>. SEE ALSO
Apache::Session::File, Apache::Session::Flex, Apache::Session::DB_File, Apache::Session::Postgres, Apache::Session perl v5.10.1 2010-10-18 Apache::Session::Oracle(3pm)
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