|Evaluating Statistics for the System and Applications / Using VSD to Analyze Statistics|
Using application-based statistics provides the most control over throughput and latency measurement. This type of measurement is possible in peer clients.
An example follows. For more information, see application-based statistics.
The following VSD chart shows an application-defined statistic for the number of new order transactions executed per second, aggregated over 180 clients. Each new order transaction consists of many statement executions. The dip in throughput early on is caused by an application synchronization point.
The next chart shows the instantaneous latency for the stock level transaction as the elapsed transaction time divided by the number of transactions for each sample. The average is 2.8 ms with a maximum of 7.18 ms. Each sample represents many transactions, so each data point is averaged over all transactions in the sample. If the application needed a true maximum latency, it could keep track of that in a separate statistic.