During the ADSM server installation, you allocated space for the database and recovery log and defined the allocated physical volumes to the server. However, you can define additional volumes and extend the capacity of the database or recovery log. You can add or delete database or recovery log volumes while the server is running.
Attention: You must not change the size of an allocated database or recovery log volume after it has been defined to ADSM. If you change the size of a volume by extending raw logical volumes through smit or otherwise changing the file sizes of ADSM volumes, ADSM may not initialize correctly, and data may be lost.
To add space to the database or recovery log perform the following steps:
The ADSM AIX server supports the use of either journaled file system (JFS) files or raw logical volumes for the database, recovery log, and disk storage pool volumes. The use of JFS files for these volumes, has the following advantages:
The use of JFS files for database, recovery log, and storage pool volumes requires slightly more CPU than is required for raw volumes. However, JFS read-ahead caching improves performance.
The size of the database or recovery log volumes affects space utilization, as is shown in the following examples:
You allocate four 24MB volumes for the database. For each volume, ADSM:
The available space is only 80MB out of the allocated 96MB.
You allocate four 25MB volumes for the database. For each volume, ADSM:
The available space for the database logical volume is 96MB out of the allocated 100MB, as shown in Figure 47.
Figure 47. An Example of Available Space
|
Notes:
If you already have a number of small volumes and want to consolidate the space into one large volume, see "Deleting Space from the Database or Recovery Log".
You can use the ADSM Server Utilities to format database and recovery log volumes. Double-click on the Volume Formatter, and enter a file name and size for the type of volume that you are formatting. You must still perform the next two steps:"Step 2: Defining Database or Recovery Log Volumes to ADSM" and "Step 3: Extending the Capacity of the Database or Recovery Log".
When you use the DSMFMT command from an operating system command line to format volumes, you must perform the next two steps: "Step 2: Defining Database or Recovery Log Volumes to ADSM" and "Step 3: Extending the Capacity of the Database or Recovery Log".
To allocate an additional 101MB to the database as volume VOL5, enter:
> ./dsmfmt -db vol5 101
Attention: The maximum size of the recovery log is 5GB, and the maximum size of the database is 500GB. If you allocate a volume that would cause the recovery log or database to exceed these sizes, the subsequent DEFINE DATABASE or DEFINE LOGVOLUME command for the volume will fail.
To define a database volume named VOL5, enter:
define dbvolume vol5
When VOL5 is defined, it becomes a part of the logical view of the server database. Thus, the server still sees a single logical database volume, which is now composed of five physical volumes. Because 1MB from VOL5 is used for overhead process, 100MB is added to the database to increase the available space to 196MB. However, the assigned capacity remains at 96MB, and ADSM cannot use the space until the capacity is extended (see "Step 3: Extending the Capacity of the Database or Recovery Log").
After you define your volumes, you can verify the change by querying the database or recovery log. For example, to query the database, enter:
query db
The server displays a report, like this:
+--------------------------------------------------------------------------------+ |Available Assigned Maximum Maximum Page Total Used %Util Max. | | Space Capacity Extension Reduction Size Pages Pages %Util | | (MB) (MB) (MB) (MB) (bytes) | |--------- -------- --------- --------- ------- --------- --------- ----- ----- | | 196 96 100 92 4,096 24,576 86 0.3 0.3 | | | +--------------------------------------------------------------------------------+
In the information displayed, the value in the maximum extension field should equal the available space of the new volume. In this example, a 101MB volume was allocated. This report shows that the available space has increased by 100MB; the assigned capacity is unchanged at 96MB; and the maximum extension is 100MB. Figure 48 illustrates these changes.
Figure 48. Adding Volumes Increases Available Space
 |
You can also use the QUERY DBVOLUME and QUERY LOGVOLUME commands to display information about the physical volumes that make up the database and recovery log.
You can only extend the database or recovery log in 4MB increments. If you do not specify the extension in 4MB increments, ADSM rounds up to the next 4MB partition. Thus, if you specify 1MB, ADSM extends the capacity by 4MB.
For example, to increase the capacity of the database by 100MB, enter:
extend db 100
When you extend the database or recovery log, ADSM starts a background process to format the new space. You can issue a QUERY PROCESS command to check on the status of the process.
The result of this command is that the assigned capacity of the database is increased by 100MB, and now equals the available space, as shown in Figure 49.
Figure 49. Extending the Capacity of the Database
 |
You can query the database or recovery log (QUERY DB and QUERY LOG commands) to verify their assigned capacities. The server would display a report, like this:
+--------------------------------------------------------------------------------+ |Available Assigned Maximum Maximum Page Total Used %Util Max. | | Space Capacity Extension Reduction Size Pages Pages %Util | | (MB) (MB) (MB) (MB) (bytes) | |--------- -------- --------- --------- ------- --------- --------- ----- ----- | | 196 196 0 192 4,096 50,176 111 0.2 0.2 | | | +--------------------------------------------------------------------------------+
After the database has been extended, the available space and assigned capacity are both equal to 196MB.