How to Improve Performance in Proxy Server 2.0 (261212)

SUMMARY

This article lists options you can use to monitor and improve the performance of Proxy Server 2.0 with Performance Monitor. Note that this article assumes that you are using a dedicated computer as the proxy server. Microsoft recommends that you set up a performance baseline. This is a set of data used to discover and scale performance issues. Establish the performance baseline during a period with a typical load. To do this, use Performance Monitor (to run Performance Monitor, click Start, point to Programs, point to Administrative Tools, and then click Performance Monitor).

Before you use Performance Monitor, make sure that the Simple Network Management Protocol (SNMP) service is installed. To install SNMP, click Start, point to Settings, click Control Panel, double-click Services, and then add the SNMP service. When you reboot the computer, you receive an error message. Follow the instructions in the following Microsoft Knowledge Base article:

163595 SNMP Entry Point Not Found

After you follow these instructions, you can use Performance Monitor. For additional information about setting up a Performance Monitor log, click the article number below to view the article in the Microsoft Knowledge Base:

150934 How to Create a Performance Monitor Log for NT Troubleshooting

The following objects and counters are described in this article:

Object: System / Counter: Processor Queue Length
Object: Web Proxy Server Service / Counter: Cache Hit Ratio
Object: Logical Disk / Counter: Current Disk Queue Length
Object: Web Proxy Server Service / Counter: Maximum Users
Object: Web Proxy Server Service / Counter: Current Average Milliseconds/request
Object: Network Interface / Counter: Output Queue Length

MORE INFORMATION

Object: System / Counter: Processor Queue Length

If the Processor Queue Length counter consistently shows a value of two or higher, you should upgrade to a faster CPU. If the computer is used only as a proxy server (recommended), it is unlikely that the CPU has a high utilization. For information about the minimal hardware requirements for Proxy Server, see the following Microsoft Web site:

http://www.microsoft.com/downloads/details.aspx?familyid=EB1993D6-EF01-44ED-9D1A-21F9B4689BC2&displaylang=en

Object: Web Proxy Server Service / Counter: Cache Hit Ratio and Object: Logical Disk / Counter: Current Disk Queue Length

You can improve the Cache Hit Ratio count by increasing the percentage of user requests for FTP and HTTP objects. These requests should be satisfied from the cache. To ensure that the most frequently requested objects can be resolved from the cache, create cache filters for the most popular sites and set their filtering status to Always Cache. To identify these sites, you can enable logging to a file. Do not log to an SQL/ODBC database because the associated performance impact is noticeable. To increase the Time To Live (TTL) value for cached objects so that they expire later and can be used longer, enable the Fewer Network Accesses are More Important (More Cache Hits) option for the Cache Expiration policy.

If the Cache Hit Ratio count is consistently high and the Current Disk Queue Length count is four or higher, the disk is not processing input/output requests in a timely fashion. Spread the cache over multiple disks or upgrade to a faster disk (for example, upgrade an IDE disk to a faster SCSI disk).

Object: Web Proxy Server Service / Counter: Maximum Users

To handle more than about 2,000 LAN computers, or as an ISP, more than about 1,000 dial-up users, consider using a proxy array instead of a single proxy server. The Maximum Users counter shows how many users are using the Web proxy simultaneously.

Object: Web Proxy Server Service / Counter: Current Average Milliseconds/request

This counter can be high for reasons other than a large number of users using Web proxy. Using a slow computer can also increase the Current Average Milliseconds/request counter.

Object: Network Interface / Counter: Output Queue Length

This counter displays the number of protocol packets in the output queue. If this counter is permanently more than two, upgrade to a new network adapter.

REFERENCES

146005 Optimizing Windows NT for Performance

150934 How to Create a Performance Monitor Log for NT Troubleshooting

163595 SNMP Entry Point not Found