Posted by editor
on September 21, 2009 at 8:04 AM PDT
In her latest article, Janice Heiss interviews Java Champion Kirk Pepperdine on Performance Tuning and Cloud Computing...
In her lastest article, Janice Heiss interviews Java Champion Kirk Pepperdine on Performance Tuning and Cloud Computing . I was in the java.net booth at this year's JavaOne when Kirk gave a presentation on Java performance tuning (you can listen to the podcast ). While "the cloud" was a significant topic at JavaOne, Kirk's java.net Community Corner presentation did not include that.
Early in the interview, Janice asked Kirk: "What misconceptions do you encounter among developers about performance tuning?"
Kirk's response wasn't what I would have expected. He answered:
Here's a major one: All developers believe they are good at performance tuning. They might be very good at writing performance code, and they might be very good at coding, but generally I find that most developers are not very good at performance tuning.
How can this be?
When developers are put in situations where they are asked to performance tune, they typically look at code and take some action. But they invariably forget the dynamics of the system. If you don't include the dynamics of the system when you performance tune or if you think you understand the dynamics of the system and guess wildly wrong - which is quite often the case - you end up doing the wrong thing, which frequently happens.
Kirk notes that software testers tend to be more successful when it comes to performance tuning than most developers, because they are more accustomed to working within a defined process.
Toward the end of the interview, Janice brings up the cloud:
As we move toward an era of cloud computing, what should Java developers understand about performance tuning? What scaling problems must developers address these days?
From his response, I think we know which choice Kirk would select in our current poll, which asks What's you opinion of 'the Cloud'? Kirk answered:
Cloud computing doesn't look that different from large data centers, which people have been trying to deal with for a long time.
While there are some problems that are peculiar to cloud computing today, I don't think they will be problems for a long time. Everyone knows that virtualization of the network is problematic. People are working hard to find ways to eliminate the problem.
There's a lot more interesting material in Janice's interview with Kirk . Read the complete interview, and you'll see what I mean.
-- Kevin Farnham
In his post Josh Bloch on the Semantic Gap , Bill Venners provides commentary on the Mind the Semantic Gap workshop that took place at last week's JVM Languages Summit :
At the JVM Languages Summit, Josh Bloch expressed his concern about what he called the "semantic gap" between the source code we write and its performance at runtime: As performance improves, our ability to predict the performance consequences of our source code degrades...
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that will take place on Wedndesday:
Arun will give a Webinar on deploying Rails Applications to GlassFish next Wednesday. Details at the Registration Page and at
Arun's post ...
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Our current Spotlight is the new Janice Heiss interview with "Java Champion Kirk Pepperdine on Performance Tuning and Cloud Computing" : "java.sun.com (JSC): In your talks, you always warn developers that they must carefully evaluate any generic advice that you provide to see if it applies to a particular situation. Why is this so important? Pepperdine: While I do give generic advice, I carefully explain that people have to evaluate it to see if it will work. I am giving advice in a vacuum, so what may work for many people most of the time may be very detrimental in other contexts. I don't know in advance what specific problem someone is working on..."
The current java.net Poll , which was submitted by Geertjan Wielenga, asks "What's your opinion of 'the Cloud'?" The poll will run through Thursday.
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The latest Java Mobility Podcast is Java Mobile Podcast 87: Tranqueira project used LWUIT : "Eloi Junior from Brazil has just opened the Tranqueira project and shares his experience in using LWUIT."
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