Monitoring the Logical Log for Fullness

You can use the following command-line utilities to monitor logical-log files.

onstat -l

The onstat -l utility display consists of the following three sections: physical-log information, logical-log information (general), and information on the individual logical-log files.

The third section contains the following information for each logical-log file:

• The address of the logical-log file descriptor
• The logical-log file number
• Status flags that indicate the status of each log

  Flags indicate whether the log is free, backed up, current, and so on.

• The unique ID of the log
• The beginning page of the log file
• The size of the log file in pages, the number of pages used, and the percentage of pages used

For information on the onstat -l option, see the utilities chapter in the IBM Informix: Administrator's Reference. Figure 87 shows sample output.

...

address  number   flags    uniqid   begin        size     used    %used
846640   1        F------  0        100233        250        0     0.00
84665c   2        F------  0        10032d        250        0     0.00
846678   3        U---C-L  3        100427        250      175    70.00
846694   4        F------  0        100521        250        0     0.00
8466b0   5        F------  0        10061b        250        0     0.00

onutil CHECK RESERVED DISPLAY

The database server stores logical-log file information in the reserved pages dedicated to checkpoint information. Because the database server updates this information only during a checkpoint, it is not as recent as the information that the onstat -l option displays. For more details on using these options to display reserved-page information, see the utilities chapter in the IBM Informix: Administrator's Reference.

You can view the checkpoint reserve pages with the onutil CHECK RESERVED command with the DISPLAY option. The following example shows sample output.

Log file number                1
Unique identifier              1
Log file flags                 0x5       Log file in use
&                                        Logfile has been backed up
Physical location              1:565
Log size                       2000 (p)
Pages used                     2000
Date/time file filled          01/07/2004 12:56:53
Time stamp when filled         0x30f8
Log slice ID                   -
Log file number                2
Unique identifier              2
Log contains last checkpoint:  Page 2, byte 0x38
Log file flags                 0x3       Log file in use
&                                        Current log file
Physical location              1:2565
Log size                       2000 (p)
Pages used                     3
Date/time file filled          -
Time stamp when filled         -
Log slice ID                   -