Transactions per Hour
Hourly Transactions per Hour Graph.
The Transactions per Hour graph shows the average number of transactions for all users per
hour. You can chose up to 31 days worth of data to display on this graph.
Under the Facts section, you see the average transaction characteristics for the current and
previous two months. It can be useful to observe the changes in the characteristics from month
to month.
A transaction must wait for a synchronous disk I/O to complete before it can continue processing.
On the other hand, a transaction can continue processing when an asynchronous I/O is
requested. As a result, even the asynchronous I/O may affect the transaction response time.
Transaction response times can increase over time if transactions require more synchronous I/O.
An increase in page fault rates is a common cause of the increase in synchronous I/O. The
addition of logical views that require immediate maintenance of the view (an index) is another
cause of the increase in synchronous I/O’s.
68
PM for Power Systems Graph Reference Document