You can use the Windows NT Performance Monitor utility to monitor your Web server's performance. Performance Monitor contains counters that monitor the activity of specific objects, that is, specific services or mechanisms controlling server resources. Counters monitor activity that varies over time, such as file transfer rates, bandwidth usage, or connection rates. For detailed information about using the Performance Monitor tool itself, see the Windows NT documentation.
Windows NT includes a number of counters, and IIS installs special counters, including Web service counters, FTP service counters, and global counters for Internet Information Services. This topic lists and describes the Web service counters.
Note While adding counters in the Add To dialog box in Performance Monitor, you can view an explanation of the currently selected counter by clicking the Explain button.
Note To obtain and use counters related to TCP, see the Windows NT Resource Kit documentation. These counters, along with disk counters also provided by the Windows NT Resource Kit, can supplement the information obtained from the counters listed here.
Counters related to bandwidth usage by Web sites are listed below. To view these counters, follow the procedure outlined in Viewing Current Performance; for Object, select Web Service, and for Instance select an instance or, to monitor all Web sites at once, select _Total.
| Counter | Description |
|---|---|
| Current Blocked Async I/O Requests | Current number of requests that are temporarily blocked by the bandwidth throttle setting. Blocked requests are held in a buffer and then unblocked if more bandwidth becomes available, unless a timeout limit is reached. |
| Measured Async I/O Bandwidth usage | The number of bytes received and sent by your Web server, averaged over one minute. This is a measure of the total amount of user traffic on your Web server. |
| Total Allowed Async I/O Requests | The number of user requests allowed by the Web service since service startup. When you throttle bandwidth, the number of allowed user requests will be restricted. |
| Total Blocked Async I/O Requests | The total number of requests that have been temporarily blocked by the bandwidth throttle setting since service startup. Blocked requests are held in a buffer and then unblocked if more bandwidth becomes available, unless a timeout limit is reached. |
| Total Rejected Async I/O Requests | The total number of user requests rejected (because of bandwidth settings) since service startup. When a request is rejected, it is not held in a buffer, unlike a blocked request. |
Counters related to throughput for Web sites are listed below. To view these counters, follow the procedure outlined in Viewing Current Performance; for Object, select Web Service, and for Instance select an instance or, to monitor all Web sites at once, select _Total.
| Counter | Description |
|---|---|
| Bytes Received/sec | Rate at which data bytes are received by the Web service. |
| Bytes Sent/sec | Rate at which data bytes are sent by the Web service. |
| Bytes Total/sec | Rate of total bytes/sec transferred by the Web service (sum of bytes sent/sec and bytes received/sec). |
| Files/sec | Rate of files transferred by server since startup of the Web service. |
| Files Received/sec | Rate of files received by (uploaded to) the Web service since the service started. |
| Files Sent/sec | Rate of files sent by (downloaded from) the Web service since the service started. |
| Total Files Received | The total number of files received by the Web service since the service started. |
| Total Files Sent | The total number of files sent by the Web service since the service started. |
| Total Files Transferred | The total number of files transferred by the Web service since the service started. Total Files Transferred is the sum of Files Sent plus Files Received. |
Counters related to specific request types, such as HTTP GET requests or CGI requests, are listed below, along with counters related to not-found errors. To view these counters, follow the procedure outlined in Viewing Current Performance; for Object, select Web Service, and for Instance select an instance or, to monitor all Web sites at once, select _Total.
| Counter | Description |
|---|---|
| CGI Requests/sec | The rate of CGI requests that are simultaneously being processed by the Web service. |
| Current CGI Requests | Current number of CGI requests simultaneously being processed by the service. |
| Current ISAPI Extension Requests | Current ISAPI extension requests simultaneously being processed by the service. |
| Delete Requests/sec | The rate HTTP requests using the DELETE method are made. |
| Get Requests/sec | The rate of HTTP requests using the GET method. GET requests are generally used for basic file retrievals or image maps, though they can be used with forms. |
| Head Requests/sec | The rate HTTP requests using the HEAD method are made. HEAD requests generally indicate a client is querying the state of a document they already have to see if it needs to be refreshed. |
| ISAPI Extension Requests/sec | The rate of ISAPI Extension requests that are simultaneously being processed by the Web service. |
| Maximum CGI Requests | Largest number of CGI requests simultaneously processed by the service since service startup. |
| Maximum ISAPI Extension Requests | Largest number of ISAPI extension requests simultaneously processed by the service since service startup. |
| Not Found Errors/sec | The rate of errors due to requests that couldn't be satisfied by the server because the requested document could not be found. These are generally reported to the client with HTTP error code 404. |
| Other Request Methods/sec | The rate at which HTTP requests are made that do not use the GET, POST, PUT, DELETE, TRACE or HEAD methods. These may include LINK or other methods supported by gateway applications. |
| Post Requests/sec | Rate of HTTP requests using POST method; generally used for forms or gateway requests. |
| Put Requests/sec | The rate HTTP requests using the PUT method are made. |
| Total CGI Requests | The total number of Common Gateway Interface (CGI) requests executed since service startup. CGI requests are custom gateway executables (.exe files) the administrator can install to add forms processing or other dynamic data sources. CGI requests spawn a process on the server which can be a large drain on server resources. |
| Total Delete Requests | The number of HTTP requests using the DELETE method. |
| Total Get Requests | Total number of HTTP GET requests received by the service; GET requests are generally used for basic file retrievals or image maps, though they can be used with forms. |
| Total Head Requests | Total number of HTTP HEAD requests received by the service. HEAD requests typically indicate that a client is querying the state of a document they already have to see if it needs to be refreshed. |
| Total ISAPI Extension Requests | Total number of HTTP ISAPI extension requests received by the service. ISAPI Extension Requests are custom gateway dynamic-link libraries (DLLs), which the administrator can install to add forms processing or other dynamic data sources. |
| Total Method Requests | The number of total HTTP GET, POST, PUT, DELETE, TRACE, HEAD and other method requests. |
| Total Method Requests/sec | The rate HTTP requests using GET, POST, PUT, DELETE, TRACE or HEAD methods are made. |
| Total Not Found Errors | Number of requests that could not be satisfied by the Web service because requested document could not be found; typically reported as HTTP 404 error code to client. |
| Total Other Request Methods | The number of HTTP requests that are not GET, POST, PUT, DELETE, TRACE or HEAD methods. These may include LINK or other methods supported by gateway applications. |
| Total Post Requests | The number of HTTP requests using the POST method. Post requests are generally used for forms or gateway requests. |
| Total Put Requests | The number of HTTP requests using the PUT method. |
| Total Trace Requests | The number of HTTP requests using the TRACE method. |
| Trace Requests/sec | The rate of HTTP requests using the TRACE method are made. |
Counters related to Web site connections, logons, and users are listed below. To view these counters, follow the procedure outlined in Viewing Current Performance; for Object, select Web Service, and for Instance select an instance or, to monitor all Web sites at once, select _Total.
Note For all counters monitoring connection activity, the counts are the total for all Web sites, regardless of what you choose for Instance.
| Counter | Description |
|---|---|
| Anonymous Users/sec | The rate users are making anonumous connections using the Web service. |
| Connection Attempts/sec | The rate that connections using the Web service are being attempted. The count is the average for all Web sites combined, regardless of what you choose for Instance. |
| Current Anonymous Users | The number of users who currently have an anonymous connection using the Web service. If a client request for an anonymous connection is rejected and the client responds with valid authenticating data, the connection is counted as non-anonymous. |
| Current Connections | The current number of connections established with the Web service (sum of anonymous and non-anonymous users). The count is the current total for all Web sites combined, regardless of what you choose for Instance. |
| Current NonAnonymous Users | The number of users who currently have a non-anonymous connection using the Web service. If a client request for an anonymous connection is rejected and the client responds with valid authenticating data, the connection is counted as non-anonymous. |
| Logon Attempts/sec | The rate at which logon attempts are being made to the Web service. |
| Maximum Anonymous Users | The maximum number of users who established concurrent anonymous connections using the Web service (since service startup). |
| Maximum Connections | The largest number of simultaneous connections established with the Web service since service startup. The count is the maximum for all Web sites combined, regardless of what you choose for Instance. |
| Maximum NonAnonymous Users | The maximum number of users who established concurrent non-anonymous connections using the Web service (since service startup). |
| Non Anonymous Users/sec | The rate at which non-anonymous users are connecting to the Web service. |
| Total Anonymous Users | The total number of users who established an anonymous connection with the Web service (since service startup). If a client request for an anonymous connection is rejected and the client responds with valid authenticating data, the connection is counted as non-anonymous. |
| Total Connection Attempts |
The total number of connections to the Web service that have been attempted since service startup. The count is the total for all Web sites combined, regardless of what you choose for Instance. This number does not include connection attempts that failed at the TCP (transport) or IP (network) layer. To monitor all connection attempts, use the Connection counters on the TCP performance object; for information about obtaining and viewing this object, see the Windows NT Resource Kit. To monitor currently active connections, use Current Connections. |
| Total Logon Attempts | The total number of successful logons to the Web service since the service started; does not include failed logon attempts. To calculate failed attempts (where clients were able to connect but not log on), subtract Logon Attempts from Connection Attempts. |
| Total NonAnonymous Users | The total number of users who established a non-anonymous connection with the Web service (since service startup). If a client request for an anonymous connection is rejected and the client responds with valid authenticating data, the connection is counted as non-anonymous. |
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