Java IO Performance

I thought I’d share a good article I just read on IO performance in a Java environment. It compares buffered versus non-buffered streams, both of which are synchronized for thread-safety, versus file channels which are unsynchronized. Going one step further, it also benchmarks the effect that buffer sizes (or “chunked” reads) have in each of those scenarios, as well as the consequence of memory-mapping those buffers.

The comparison to some of the predominant ways to read files in C towards the end adds some nice perspective.

http://nadeausoftware.com/articles/2008/02/java_tip_how_read_files_quickly

Jopr has embedded database support!

Jopr now supports an embedded database option during installation (using H2 under the covers). This option, aside from preparing the embedded database, also configures an embedded agent running inside the same VM. This means it takes only a few keystrokes now to install an entire Jopr system, end-to-end.

The bits can be found here.

Quick install steps:

• download & unzip the jopr-server-2.2.1.zip binary
• start the server using scripts at the top-level bin dir
• go to http://localhost:7080/
• click the “Embedded Mode” button at the top at the page (this enables the embedded db *and* the embedded agent)
• click the install button at the bottom of the page

Comments and questions welcome on the Jopr forums.

Note: the embedded database and embedded agent options are not intended production use. They were developed to facilitate quick installs so that new users could easily demo the product, or existing users get a quick overview of what features the latest distribution has to offer. At the time of this writing, there is no upgrade support when choosing the embedded mode option.

Don’t reinvent the wheel

I can’t help but relish from time to time how powerful the Jopr / RHQ platform is. When you look at a product like Tomcat you might think that to write an end-to-end management framework around it would take a few man years at best.

Not so with Jopr / RHQ. Instead of spending time worrying about the ins and outs of how to move metric data around your network (and subsequently graph it), how to send a remote method execution down to your server, how to be notified when certain events take place on your servers, how to audit what users do and/or control who does what – you get all of that out-of-box with Jopr / RHQ.

So what does this all mean? It means that by leveraging a robust management platform like Jopr / RHQ you get to focus on what’s important – the servers you’re managing.

Jay Shaughnessy, a colleague of mine, provided the most recent proof of these claims. He wrote a plugin for end-to-end management of Tomcat. By leveraging Jopr / RHQ, he was able to accomplish an impressive amount in a relatively short period of time. But I’ll let him tell you about it…

http://jayshaughnessy.blogspot.com/2009/04/jopr-22-adds-tomcat-management.html