1 – AIJ file writes field
This field gives the total number of write-I/Os (queued I/O requests) issued to the database after-image journal (.aij) file. The "data," "control," "file extend," and "switch over" counts further subdivide the statistic.
2 – ____data_field_
This field gives the number of write-I/Os to the database after- image journal file that contained only data records.
3 – ____control_field_
This field gives the number of write-I/Os to the database after- image journal file that contained OPEN, COMMIT, ROLLBACK, and checkpoint records. These writes may also include data records.
4 – ____file_extend_field_
This field gives the number of write-I/Os issued to the database after-image journal file to initialize new disk blocks when the file is extended.
5 – ____switch_over_field_
This field gives the number of times AIJ switch-over has occurred (the number of times journaling has switched from one journal file to another).
6 – tx__block_span_field
This field displays the number of blocks each transaction spans in the AIJ journal.
7 – records_written_field
This field gives the number of logical after-image journal records written to the after-image journal file. Because many logical records can be buffered into a single write-I/O, this number is usually much larger than the number of .aij file writes. No count is kept for the number of logical AIJ records read by the DBR process.
8 – blocks_written_field
This field gives the number of disk blocks written to the after- image journal file. Because many disk blocks may be written with a single write-I/O, this number may be larger than the number of .aij file writes. In addition, the same disk block can be written more than once, because it might not have been completely full the first time it was written.
9 – ____filler_bytes_field_
This field gives the number of filler bytes (bytes that contain nothing, that is, memory allocated but not used) needed to pad AIJ records to a disk block boundary. Filler bytes are necessary to ensure the readability of the after-image journal file in the event of a system failure during a write-I/O operation.
10 – lock_rebuilds_field
This field gives the number of times that the after-image journal lock value block had to be rebuilt. The AIJ lock value block contains the current end-of-file information about the after- image journal file. The lock value block can be lost when there is a VMScluster configuration change, or when a user process holding the lock terminates abnormally (with a Ctrl-Y/STOP, for example).
11 – AIJ file reads field
This field gives the number of read-I/Os executed during lock rebuilds. To rebuild the lock value block, the after-image journal file is read backwards to find the last record in the file.
12 – shuffle_averted_field
This field displays the number of times the group commit buffer has had a shuffle operation averted. The shuffle operation can be averted for a number of reasons, including setting the RDM$BIND_ AIJ_SHUFFLE_DISABLED logical name to the value "0".
13 – suspended_switch_field
This field displays the number of times the AIJ switchover operation enters the suspended state. A database enters the "AIJ suspended" state when the AIJ switch- over operation cannot complete because there are no available AIJ journals. During this state, the DBA can add new AIJ journals or perform database backups, but all other AIJ-related activities are temporarily suspended until an AIJ journal becomes available.