Response Time

[Guest Xpandqa]

Can someone explain the difference between Avg and Avg90 concerning page Response time on Summary reports?

I see the Avg90 response time always greater that Avg response time.

[Guest angela]

As for the difference between Avg and Avg90, the latter means average response time calculated for 90% of all participated users.

Thus, Avg90 not only can be greater than Avg, it always should be equal or greater than Avg. So your case is normal. If you feel that it is not, please send to us your scenario, profile and results file .

[Guest Brad]

What is the purpose of Avg90? Why do I care about that measure? Thanks.

[Guest angela]

What is the purpose of Avg90? Why do I care about that measure? Thanks.

 

Hi, Avg90 is so called 90 percentile (a statistical value): http://www.childrensmercy.org/stats/defini...percentiles.htm

 

Roughly speaking, we use 90 percentile when we need to know statistics not for all, but for "nearly all" virtual users.

Or, for instance, imagine the situation when server responds quickly all the time, but sometimes produces a very slow response. As such responses happen too rarely you possibly don't care about them. And WAPT, when calculating Avg90, doesn't take them into acount. So looking at Avg90 you can understand how happy are the users working with your web site "nearly all" time.

[Guest Mark]

Hi, Avg90 is so called 90 percentile (a statistical value): http://www.childrensmercy.org/stats/defini...percentiles.htm

 

Roughly speaking, we use 90 percentile when we need to know statistics not for all, but for "nearly all" virtual users.

Or, for instance, imagine the situation when server responds quickly all the time, but sometimes produces a very slow response. As such responses happen too rarely you possibly don't care about them. And WAPT, when calculating Avg90, doesn't take them into acount. So looking at Avg90 you can understand how happy are the users working with your web site "nearly all" time.

 

 

This seems contradictory to what you said on the above post that Avg90 will always be greater than the Average.... if you are removing the highest times (longest 10% of all requests) then your Avg90 should always be less than the average, no?

[Guest angela]

This seems contradictory to what you said on the above post that Avg90 will always be greater than the Average.... if you are removing the highest times (longest 10% of all requests) then your Avg90 should always be less than the average, no?

 

 

It seems that you believe that Avg90 is an average between all values after removing from them longest 10%. It is not quite so.

 

Avg90 calculated in the following way:

 

1) We remove the highest times (longest 10% of all requests).

2) The highest time of remaining ones will be Avg90.

 

In general, it is possible that Avg is greater than Avg90. But it can happens in case of a significant difference between the min and the max values. But it happens quite rarely, usually values do not differ much, and, thus, usually Avg is less than Avg90.

 

[Guest Mark]

It seems that you believe that Avg90 is an average between all values after removing from them longest 10%. It is not quite so.

 

Avg90 calculated in the following way:

 

1) We remove the highest times (longest 10% of all requests).

2) The highest time of remaining ones will be Avg90.

 

In general, it is possible that Avg is greater than Avg90. But it can happens in case of a significant difference between the min and the max values. But it happens quite rarely, usually values do not differ much, and, thus, usually Avg is less than Avg90.

 

 

Thanks so much Angela! Very clear definition.