IIS Web Server Test

This internal test complements the measurements made from an external perspective by the Http test. It collects various statistics that measure the request load on the web server and its responsiveness to the load. The statistics collected by this test are detailed below:

Target of the test : A web server instance

Agent deploying the test : An internal agent;

Outputs of the test : One set of results for every web server monitored

Configurable parameters for the test
  1. TEST PERIOD - How often should the test be executed
  2. Host - The host for which the test is to be configured
  3. Port - the port to which the specified host listens
Measurements made by the test
Measurement Description Measurement Unit Interpretation


Rate of connections to the web server.


An increase or decrease in connection rate can represent a change in user workload


Rate of requests to the web server during the last measurement period.


With the advent of HTTP/1.1, multiple requests can be transmitted over the same TCP connection. The ratio of requests per connection can provide an idea of the effectiveness of the HTTP 1.1 protocol.

Data transmitted:

Rate at which the data was transmitted by the server during the last measurement period.


A large increase in the data transmission rate can be indicative of an increase in the popularity of one or more web sites hosted on the server.

Data received:

Rate at which the data was received by the server during the last measurement period.


An increase in this value is indicative of an increase in user requests to the server.


Percentage of error responses from the server during the last measurement period.


This is the percentage of errors that occurred due to requests that couldn't be satisfied by the server because the requested document could not be found.

400 errors:

Percentage of responses with a status code in the range 400-499 during the last measurement period.


A high value indicates a number of missing/error pages.

Current requests:

Number of server threads/processes currently in use for serving requests (this measurement is not available for Apache web servers).


If a majority of the server threads/processes are in use simultaneously, this may be indicative of a server bottleneck.


The Web Server test will report metrics for an IIS web server executing on a Windows 2008 host, only if the IIS Management Scripts and Tools feature is installed on that host, and the Web Server role you create enables this feature. If the aforesaid feature is not enabled for the Web Server role, then remove the role and re-create it with the feature enabled.