Updates

“Updates” reports the number of deferred and direct row updates. The “% of total” column reports the percentage of each type of update as a percentage of the total number of row updates. sp_sysmon reports the following types of updates:

Direct updates incur less overhead than deferred updates and are generally faster because they limit the number of log scans, reduce locking, save traversal of index B-trees (reducing lock contention), and can save I/O because Adaptive Server does not have to refetch pages to perform modification based on log records.

For a description of update types, see “How update operations are performed” on page 92 in Performance and Tuning: Optimizer.

If there is a high percentage of deferred updates, see “Optimizing updates” on page 100 of the same book.


Total rows updated

“Total Rows Updated” reports all deferred and direct updates combined. The “% of total” columns shows the percentage of rows updated, based on all rows modified.