IIS Monitor

Applies to ReadyAPI 3.53, last modified on May 15, 2024

You use IIS monitors to check metrics of your IIS servers.


To monitor an IIS server, you need to prepare it in the same way you prepare Windows servers for testing:

  • ReadyAPI must run on a Windows machine. Windows, IIS and MSSQL monitors are not available on Linux and macOS machines.

  • The Remote Registry service must be enabled on the server.

  • Ports 139 and 445 must be open on the server, the computer with ReadyAPI and any proxy between them.

  • The user account must have Performance Monitor or Administrator permissions on the server.

For detailed information, see Preparing Servers for Monitoring.

Monitor Settings

The monitor does not have settings.

Frequently Used Metrics

The IIS monitor provides information about user interaction with the server. ReadyAPI displays the following statistics in charts by default:

  • Web Service – Current Connections – Total – The current number of connections to the server. This value should be the same as the number of virtual users you simulate.

  • Web Service Cache – Kernel – URI Cache Hits – The number of hits to the cached URIs. It is generally preferred to have this value as high as possible. However, if your server cannot store the response cache, this value should be low.

Here are some other frequently used metrics:

  • Web Service – Service Uptime – Measures the period of time during which the server has been running. Most servers need to be regularly rebooted for installation of updates and for maintenance. A server with long uptime may cause performance issues.

  • Web Service – Locked Errors/sec – Measures the number of requests which failed because the requested resources were already in use. The resources may be in use, or "locked" if the previous request did not free them up before the server tried to handle the next request in the queue.

  • Web Service Cache – Current File Cache Memory Usage – Measures the amount of memory used by the web service cache. The files are cached to increase the speed of access, but, if there is not enough memory in your server, this may cause performance issues.

Other Metrics

ReadyAPI can access the Web Service and Web Service Cache PerfMon objects and their respective counters. You can find a full reference to IIS 6.0 counters on the Microsoft web site. The following statistics are usually available:

Category Description Metrics

Web Service

Provides information about active web services. One set of statistics per service, and one for total among all servers.

Anonymous Users/sec

Bytes Received/sec

Bytes Sent/sec

Bytes Total/sec

CGI Requests/sec

Connection Attempts/sec

Copy Requests/sec

Current Anonymous Users

Current Blocked Asyn I/O Requests

Current Blocked Bandwidth Bytes

Current CAL Count for Authenticated Users

Current CAL Count for SSL Connections

Current CGI Requests

Current Connections

Current ISAPI Extension Requests

Current Non-anonymous Users

Delete Requests/sec

Files Received/sec

Files Sent/sec


Get Requests/sec

Head Requests/sec

ISAPI Extension Requests/sec

Lock Requests/sec

Locked Errors/sec

Logon Attempts/sec

Maximum Anonymous Users

Maximum CAL Count for Authenticated Users

Maximum CAL Count for SSL Connections

Maximum CGI Requests

Maximum Connections

Maximum ISAPI Extension Requests

Maximum Non-anonymous Users

Measured Async I/O Bandwidth Usage

Mkcol Requests/sec

Move Requests/sec

Non-anonymous Users/sec

Not Found Errors/sec

Options Requests/sec

Other Request Methods/sec

POST Requests/sec

Propfind Requests/sec

Proppatch Requests/sec

PUT Requests/sec

Search Requests/sec

Service Uptime

Total Allowed Async I/O Requests

Total Anonymous Users

Total Blocked Async I/O Requests

Total Blocked Bandwidth Bytes

Total Bytes Received/sec

Total Bytes Sent/sec

Total Bytes Total/sec

Total CGI Requests/sec

Total Connection Attempts/sec

Total Copy Requests/sec

Total Count of Failed CAL Requests For Authenticated Users

Total Count of Failed CAL Requests For SSL Connections

Total Delete Requests

Total Files Received

Total Files Sent

Total Files Transferred

Total GET Requests

Total Head Requests

Total ISAPI Extension Requests

Total Lock Requests

Total Locked Errors/sec

Total Logon Attempts/sec

Total Method Requests

Total Method Requests/sec

Total Mkcol Requests/sec

Total Move Requests

Total Nonanonymous users

Total Not Found Errors/sec

Total Options Requests/sec

Total Other Request Methods/sec

Total POST Requests/sec

Total Propfind Requests/sec

Total Proppatch Requests/sec

Total PUT Requests/sec

Total search Requests/sec

Total Trace Requests

Total Unlock Requests

Trace Requests/sec

Unlock Requests/sec

Web Service Cache

Provides information about stored web services cache

Active Flushed Entries

Current File Cache Memory Usage

Current Files Cached

Current Metadata Cached

Current URLs Cached

File Cache Flushes

File Cache Hits

File Cache Hits %

File Cache Misses


  • Current URLs Cached

  • Total Flushed URLs

  • Total URLs Cached

  • Total URL Cache Flushes

  • URL Cache Hits

  • URL Cache Hits %

  • URL Cache Hits/sec

  • URL Cache Misses

Maximum File Cache Memory Usage

Metadata Cache Flushes

Metadata Cache Hits

Metadata Cache Hits %

Metadata Cache Misses


  • Current Flushed Items

  • Current Hits %

  • Current Items

  • Current Memory Usage

  • Total Flushed Items

  • Total Flushes

  • Total Hits

  • Total Misses

Total Files Cached

Total Flushed Files

Total Flushed Metadata

Total Flushed URLs

Total Metadata Cached

Total URLs Cached

URL Cache Flushes

URL Cache Hits

URL Cache Hits %

URL Cache Misses

See Also

Preparing Servers for Monitoring
Server Inspector
Load Testing Templates

Highlight search results