A transaction that requires more space than is available for the requesting user ends abnormally. When you create a user or database, the system requests space from the pool of free cylinders. To protect transactions, you can specify that a number of cylinders be reserved for transactions needing permanent space.
When a statement requires space, this field determines allocation as described in the following table.
| Statement Need | Free Cylinders | Result |
|---|---|---|
| Permanent space | One or more | Statement succeeds. |
| Less than one | Statement fails with a disk full error. | |
| Spool space | More than the amount specified in Cylinders Saved for PERM | Statement succeeds. |
| Fewer than the amount specified in Cylinders Saved for PERM | Statement fails with a disk full error. |
Therefore, requests needing SPOOL space may fail more often than requests needing PERM space. This can be advantageous because failure of a request for spool space rarely involves a rollback.