Adding a chunk to a dbspace or blobspace

You add a chunk when a dbspace, blobspace, or sbspace is becoming full or requires more disk space.

Important: The newly added chunk (and its associated mirror, if one exists) is available immediately. If you are adding a chunk to a mirrored storage space, you must also add a mirror chunk.

To add a chunk using onspaces:

  1. On UNIX, you must be logged in as user informix or root to add a chunk.

    On Windows, users in the Informix-Admin group can add a chunk.

  2. Ensure that the database server is in online, administration, or quiescent mode, or the cleanup phase of fast-recovery mode.
  3. Allocate disk space for the chunk, as described in Allocate disk space.
  4. To add a chunk, use the -a option of onspaces.

    If the storage space is mirrored, you must specify the path name of both a primary chunk and mirror chunk.

    If you specify an incorrect path name, offset, or size, the database server does not create the chunk and displays an error message. Also see What to do if you run out of disk space.

  5. After you create the chunk, you must perform a level-0 backup of the root dbspace and the dbspace, blobspace, or sbspace that contains the chunk.
The following example adds a 10-megabyte mirror chunk to blobsp3. An offset of 200 KB for both the primary and mirror chunk is specified. If you are not adding a mirror chunk, you can omit the -m option.
onspaces -a blobsp3 -p /dev/raw_dev1 -o 200 -s 10240  -m /dev/raw_dev2 200
The next example adds a 5-megabyte chunk of raw disk space, at an offset of 5200 KB, to dbspace dbspc3.
onspaces -a dbspc3 \\.\e: -o 5200 -s 5120

You can also define information that Informix® can use to automatically extend the size of a chunk when additional storage space is required for an application. If you have extendable chunks, you are not required to add new chunks or spend time trying to determine which storage space will run out of space and when it will run out of space.


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