When the transaction log becomes nearly full, it may be impossible to use standard procedures to dump transactions and reclaim space. The System Administrator should monitor the log size and perform regular transaction log dumps (in addition to regular database dumps) to make sure this situation never occurs. Use the preferred method of setting up a threshold stored procedure that notifies you (or dumps the log) when the log reaches a certain capacity. See Chapter 29, “Managing Free Space with Thresholds,” for information about using threshold procedures. It is also good to dump the transaction log just prior to doing a full database dump in order to shorten the time required to dump and load the database.
You can also monitor the space used in the log segment manually by using the sp_helpsegment stored procedure, as described under “Getting information about segments”.