Just came across this post, seems pretty cool. I’ve been a fan of sFlow for quite a while now, though have not yet tried host sFlow (though have been aware of it’s existence for a year or so).
I know the pain monitoring JMX for sure, many eons ago I had a java engineer make me some bean shell scripts that allowed me to poll JMX services once every few seconds while maintaining a single JVM for days or weeks at a time, it was soooo handy. The mod-sflow for apache sounds really neat too.
I’ve also used this tiny jsp to poll tomcat heap, has worked very well without having to resort to jmx
<% Runtime runtime = Runtime.getRuntime(); %> <%=runtime.freeMemory()%> memory free of <%=runtime.totalMemory()%> total memory