com.buzzsurf.dns
Class SpeedTest

java.lang.Object
  |
  +--com.buzzsurf.dns.SpeedTest

public class SpeedTest

extends java.lang.Object

This class tests the speed of DNS resolutions by looking up the IP Addresses of multiple domain names. It reads the domain names from file you specify on the command like, 1 name per line.

There are a number of important things to consider when speed testing your DNS resolution system!

• Run this test multiple times. The first time will almost always be slower than subsequent tests, because after resolving the name once, your DNS server will cache it locally.
• Run this test with different data sets. Try using a data set with all distinct domain names, and then a data set with some duplicate domain names. Your performance should be better on the duplicate test because of local caching.
• Run this test with different thread counts to see what happens. You can place a very heavy load on a DNS server by setting the thread count high. Your DNS server may perform well at a light load, but fail during heavy load. Watch your HNF% to see this.
• Your network, DNS server, local machine, and the resolver you are using can all effect performance.
  • The standard Java 1.4 resolver uses native calls. This can be fast in some cases, but has been found to be a bottleneck under heavy load because of synchronization.
  • Does your resolver use TCP or UDP by default? TCP based resolvers are generally much slower.
  • What kind of DNS server are you using? Our tests have shown that Bind 9 is a great performer, and Microsoft DNS Server ineviatably produces high HNF% over time and under load. There are other commercial solutions available that may be a good choice as well.
• It is very important that you don't consider speed alone, but also the number of failed resolutions (Host Not Founds (HNFs)) you get. We have found that your HNF% is intimately related to the current load on your DNS server.

Version:

0.9

Author:

Paul Cowan (pwc21@yahoo.com)

Constructor Summary

SpeedTest(java.lang.String inputFileName, int numThreads)

Method Summary

static void	main(java.lang.String[] args)
protected java.lang.String	nextDomain()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SpeedTest

public SpeedTest(java.lang.String inputFileName,
                 int numThreads)

Method Detail

main

public static void main(java.lang.String[] args)

nextDomain

protected java.lang.String nextDomain()