CIO Today recently covered a story of a Stanford research group analyzing the effectiveness of microbooting small parts of you application rather than the entire application server for fast failure recovery.

I had the pleasure of meeting George Candea 18 months ago at a JBoss Bootcamp in San Francisco and am glad his research has made it to the mainstream.

See more coverage in The Micro-Reboot: A Time-Saving, Inexpensive Boot in the Gear

The paper is good, but there are some holes in it. I have written them up at:
http://blogicblog.blogspot.com/2004/11/microrebooting-papers-reasoning-holes.html

I'd say that it's a nice concept, but one that needs to be architected for. It's hard to imagine gluing such a concept onto existing APIs and applications.

Humorous note -- this research was partially funded by Microsoft and IBM, but the researcher used JBoss. ;-)

Peace,

Cameron Purdy
Tangosol, Inc.
Coherence: Shared Memories for J2EE Clusters

I'd say that it's a nice concept, but one that needs to be architected for. It's hard to imagine gluing such a concept onto existing APIs and applications.

When I talked to George 2 years ago, he said they had some tools to search for "fault points".

IMO, I think detecting and successfully analyzing the fault can be as important as being able to recover from the fault. If I remember correctly, the research does talk about fault identification.

Bill

I havent read through all of the documentation, but the concepts seem extremely similar to osgi. Osgi allows multiple sub components to have independent lifecycle management ie: installed, stopped, started etc. without affecting the whole system. Perhaps I am missing the point of micro-rebooting? I think eclipse uses osgi to manage its plugins under the hood, here is another java implementation knoplerfish

greg

And you can use ogsi if you have the latest eclipse framework. It's embedded.

In the J2EE world wouldn't micro-rebooting be parallel to restarting a web app without restarting the application server or JVM instance? If so, that's been around a long time. I'd agree that simply restarting a web app is an order of magnitude quicker than the entire app-server.

In fact, even restarting the JVM is a form of micro-rebooting because usually you don't have to restart the OS too.

Maybe they are talking more about splitting up the application server into modules that can be "rebooted" but I guess I'd see that as more of a pluggable api.

Does this whole thing just boil down to the idea of making your apps (OS and frameworks too) modular so that changing the state in one has little effect on another? Programming 101?

Or am I missing something fundamentally new from the article?

In the J2EE world wouldn't micro-rebooting be parallel to restarting a web app without restarting the application server or JVM instance?

If so, that's been around a long time.

That's exactly what it is, but more deliberately so, and on a finer-grained level.

Peace,

Cameron Purdy
Tangosol, Inc.
Coherence: Shared Memories for J2EE Clusters

I thought you could already do this if you built your application around a JMX core?

-Pete

I thought you could already do this if you built your application around a JMX core?

Hi Pete, that's the difference between marketing and reality ;-)

You _could_ theoretically do this around a JMX core, but for the most part, there's nothing special about JMX that enables or prevents it ..

Peace,

Cameron Purdy
Tangosol, Inc.
Coherence: Shared Memories for J2EE Clusters

When I first started to look at JMX and bought the book "Managing J2EE with Java Management Extensions" they had a section on building reloadable components. You have to design your app. from the ground up to utilize dynamic reloading but with the decoupling of the Services it is possible. I build a couple of toy applications just to check it out. Kinda cool but most project are not planned with that in mind.

-Pete

I thought you could already do this if you built your application around a JMX core?

Hi Pete, that's the difference between marketing and reality ;-)You _could_ theoretically do this around a JMX core, but for the most part, there's nothing special about JMX that enables or prevents it .. Peace,Cameron PurdyTangosol, Inc.Coherence: Shared Memories for J2EE Clusters