On some older versions of Windows (notably Windows Server 2003), Jetty's performance can be less-than-stellar by default. To address this, the Jetty team has developed a tuning step which can make Nexus Repository 2 more responsive on old Windows platforms.
To implement this fix, modify "<nexus_root>/conf/jetty.xml", changing this:
<Call name="addConnector">
<Arg>
<New class="org.eclipse.jetty.server.nio.SelectChannelConnector">
<Set name="host">${application-host}</Set>
<Set name="port">${application-port}</Set>
</New>
</Arg>
</Call>
To this:
<Call name="addConnector">
<Arg>
<New class="org.eclipse.jetty.server.nio.SelectChannelConnector">
<Set name="host">${application-host}</Set>
<Set name="port">${application-port}</Set>
<Set name="responseBufferSize">512</Set>
</New>
</Arg>
</Call>
NOTE: full documentation for this tuning step can be found on the Jetty wiki at: http://docs.codehaus.org/display/JETTY/Slow+Win2003