Identifying Problems with a Frozen System (Informix) (SAP Library

Identifying Problems with a Frozen System (Informix)

Use

This procedure tells you how to identify the problem when your system has frozen, that is, completely stopped processing. These are the main reasons for a frozen system:

The logical-log files are full and an emergency backup is needed
Lockwait situations are occupying all work processes

Procedure

Check to see if the logical-log files are full and perform an emergency backup if so:

Check the message log in one of the following ways:

Checking the Database Message Log (Informix) in the database monitor

Listing System Information with SAPDBA

Using onstat -m as user informix

If the following message appears, you need to perform an emergency backup:

Logical Log Files are Full -- Backup is Needed

If necessary, use your normal data recovery tool – ON-Bar , ON-Archive , or ontape – to perform an emergency backup. This frees the logical logs, allowing normal system processing to continue.

To avoid this situation in future, see Preventing Emergency Logical-Log Backup.

Check to see if there is a lockwait situation.

If lock holders and waiters occupy all work processes, then even users with no interest in the locked records are prevented from working.