Kbase 12175: The Progress Shared Memory File on VMS
| Autor |
Progress Software Corporation - Progress |
| Acesso |
Público |
| Publicação |
5/10/1998 |
|
The Progress Shared Memory File on VMS
INTRODUCTION:
=============
This Technical Support KnowledgeBase entry outlines a strategy to
resolve the situation where the PROGRESS shared memory file on VMS
is "locked by another user" and the server cannot be started.
This is usually manifested by error 1260.
PROGRESS ERROR NUMBER: ERROR TEXT:
====================== ==================================
1260 Shared Memory in use by another
process.
1554 The server did not start successfully.
POSSIBLE CAUSE OF ERROR:
========================
When a PROGRESS server is brought down normally, that is,
using PROGRESS/MULTI=SHUT dbname, the .shm file is released.
When a new server is then started, the .shm file is initialized,
a snapshot of shared memory is created in the file, and normal
operations begin.
However, when an ABNORMAL termination of the database occurs
and the server crashes rather than coming down normally, the
.shm file might be left open and processes might be left in the
database. Those processes might have a lock on the .shm file.
In that event, when a new server is started, you might receive the
error 1554, "The server did not start successfully" or you might
receive error 1260, "Shared memory in use by another process".
CORRECTIVE MEASURES:
====================
To resolve this problem use the VMS utilities SHOW SYSTEM
or ANAL/SYSTEM to determine what processes are still in the
database, and still have a hold on the .shm file. Once you
find the processes, STOP/ID the processes. When all the
processes have exited from the .shm file, it is released.
You can start a new server, the .shm is re-initialized, and normal
operations are resumed.
If the shared memory file is still not released, it is
VERY likely that a process is still in the database and has
hold of the .shm file. In that event, further investigative
work must be done and the offending processes exited.
The only other option is to reboot the machine, which
clears shared memory. Renaming the <dbname>.shm file will sometimes
resolve the problem.
Once shared memory is cleared or the .shm file is released, you can
attempt to start the server again.
ONLINE PROCEDURES OR UTILITIES:
===============================
VMS Utilities: SHOW SYSTEM, ANAL/SYSTEM, SHOW DEV/FILES
REFERENCES TO WRITTEN DOCUMENTATION:
====================================
VMS System Manuals
Progress Software Technical Support Note # 12175