Polycom 3725-70003-009F Manuale Utente
Diagnostics and Troubleshooting
Proprietary & Confidential
147
Database Troubleshooting
This section suggests some methods for diagnosing the database and
investigating database problems.
investigating database problems.
Checking for Informix Server Engine Errors
To determine if an error has occurred in the Informix server engine, check the
/usr/informix/online.log file for error or panic messages, using the grep
command to search for those words.
With the standard configuration, Informix temporarily stores results data in
the /tmp directory. Lack of sufficient free space in this directory can be the
command to search for those words.
With the standard configuration, Informix temporarily stores results data in
the /tmp directory. Lack of sufficient free space in this directory can be the
cause of server engine errors.
Use the df command to check the disk space in the /tmp directory (see
Use the df command to check the disk space in the /tmp directory (see
on page 103). If it’s more than 90% full, remove
unneeded files to free up space for database data. Call your Polycom Global
Services representative if you need help in determining what you can safely
remove.
Services representative if you need help in determining what you can safely
remove.
Checking for Slow SQL Queries
If you suspect the database is slowing down the system, check for an SQL
query that takes much more time than the others:
query that takes much more time than the others:
1
In a CACS XTerm window, log in as root, switch user to informix, and set
the Informix environment by entering tcsh.
the Informix environment by entering tcsh.
2
Enter onstat –g ses.
Informix displays a list of sessions and their memory usage.
Informix displays a list of sessions and their memory usage.
3
Locate the session that uses the most memory and note its session ID.
4
Enter onstat –g sql.
Informix displays a list of active queries and their session IDs.
Informix displays a list of active queries and their session IDs.
5
Check the list of active queries for the session you identified in
. If it’s
listed, enter onstat –g sql ID (where ID is the session ID number of
the session you identified in
the session you identified in
Informix displays the running query.
6
Contact your Polycom Global Services representative to determine if this
query is taking more memory than it should.
query is taking more memory than it should.