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Back to newsletter 143 contents
Fault tolerance, redundancy, high availability. If you're a performance expert, you know these terms and what they do for your services, though even if you aren't the terms are easily understood, as they represent exactly what they say. They tend to be related to each other - a common way to handle fault tolerance is to have some redundancy, and automatically failover to a redundant component if the primary fails. A common way to have a highly available service is to make it fault tolerant and failover quickly enough that it continues to serve requests without interruption despite any failures.
Nothing illustrates fault tolerance, redundancy and high availability more than the recent SpaceX Dragon spacecraft flight to the International Space Station earlier this month. One minute and 19 seconds into the flight one of it's first stage engines failed. The spacecraft is designed to be fault tolerant and highly available - the cost of spacecraft flight failure far exceeds the cost of building redundancy and failover capability into the craft. It has nine engines where it only needs seven for normal flight (redundancy). None of the other engines nor the rocket was affected from the loss of the engine (fault tolerance). After the loss of the engine, the flight computer recomputed a new ascent profile in real time, and there was no effect on the actual mission (high availability). Awesome.
(I have to mention, the flight computer is C/C++ based, not Java. But SpaceX's last century choice of language doesn't detract from a fabulous implementation which I had to applaud here). Well done SpaceX team!
On a completely different but also awesome note, it's definitely worth you knowing that for a limited time you can get hold of an unlimited license (yes, including for commercial use!) to use the Excelsior JET JVM for just $10 - and the $10 is not even going to Excelsior, it's actually going to a Cancer care charity! It's a 99% discount off the list price - and the 1% you pay is going to help alleviate suffering. That's one awesome deal!
Now read on for all our usual links to Java performance tools, news, articles and the extracted tips from all of this month's referenced articles.
Java performance tuning related news.
Java performance tuning related tools.
Back to newsletter 143 contents
