What is 90th Percentile Response Time?
The 90th percentile response time value is the value for which 90% of the data points are smaller and 10% are bigger.
To calculate the 90th percentile value:
1. Sort the transaction instances by their value.
2. Remove the top 10% instances.
3. The highest value left is the 90th percentile.
Consider the below example:
There are 10 instances of transaction “TRANSACTION 01” with the values
| 4 sec | 2 sec | 3 sec | 1 sec | 5 sec | 17 sec | 8 sec | 7 sec | 6 sec | 10 sec |
1. Sort values from best to worst:
| 1 sec | 2 sec | 3 sec | 4 sec | 5 sec | 6 sec | 7 sec | 8 sec | 10 sec | 17 sec |
2. Remove top 10%, In our case i.e. value “17 sec”
| 1 sec | 2 sec | 3 sec | 4 sec | 5 sec | 6 sec | 7 sec | 8 sec | 10 sec |
3. The highest value left is the 90th percentile value i.e. “10 sec” is the 90th percentile value.
In loadrunner 11.5 you can also calculate 100% percentile value. Ideally maximum value observed for any tranasaction and 100% percentile value should be same? In case both are coming as different. Please let me know if my assumption is correct?
Yes. Absolutely right.
Hi,
I need further information about how 90% is calculated by Loadrunner.
When we ran a test with 100 users, the 90% response time is 16sec for login & 8 sec for logout.
But with 1 user, the 90% response time is 18 sec for login & 11 sec for logout.
Why is this variation in 90% calculation?
well written blog,superb