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Swiss Firm Claims Boost In Android App Performance
Precision writes to inform us about the Swiss firm Myriad, which claims a 3x boost in Android app performance and longer battery life with a new virtual machine. Myriad says that its technology is 100% compatible with existing Android apps. "The tool is a replacement for the Dalvik virtual machine, which ships as part of the Android platform, and retains full compatibility with existing software. Dalvik Turbo also supports a range of processors including those based on ARM, Intel Atom, and MIPS Architectures."
Check his wiki, this guy is the real deal. He is the architect of the BeOS file system, something that still hasn't been surpassed in flexibility and efficiency - the crown jewel of the BeOS code. Trolltech's QT also improved a lot under his reign. I would say that this guy knows a lot about writing optimized code, and Google should be very happy that he's turned his attention to Android. If I were Google, I'd be thinking hard about buying out this plucky little startup from Switzerland.
How to build a flawed API in Java...
If a library's performance depends strongly on GC performance, then the programmers should refactor their code to reuse existing objects rather than building new ones all the time.
The absolute worst thing you can do in an object oriented language, which is intended to be used in an object oriented way, is to instance objects without the instancing of them initializing them. The original Java Mail API did this, and it was a steaming pile because of that. I would probably go so far as to suggest that any object oriented language which permitted this was not designed correctly. To reuse the objects, you'd have to be able to reinitialize them, which is basically the same thing.
The typical problem with Java programs and garbage collectors is chasing force-zeroing of pages because they release the memory back to the system, and their security model requires that the memory be zeroed before it is reused by the program. Being a little bit time lazy about doing your GC to reclaim the memory on behalf of the system rather than on behalf of the program you are running almost always results in significant performance improvements in things like Physics engines. In other words, you want a little intentional latency between the time you collect the garbage, and the time you deliver it to the dump.
One of the most obvious recent offenders is Apache Lucene , specifically , which works just great, if you don't do the finalize() and cause the objects to be collected way too early.
So the problem usually boils down to a greedy garbage collector, which is a problem in the JVM, not the library code.
Of course on tiny platforms, the JVM footprint gets pretty large, so you'd also need to gather and LRU the freed heap to avoid it growing out of control from the latency; so you'd need a high water mark as well as a timed delay.
Personally, I really hate garbage collection as a paradigm, especially the garbage collection in Objective C. It claims to be optional, but isn't: as soon as you have one framework that doesn't do an explicit release of an object, your program is forever after addicted to the garbage collector, and slowly accumulates leaks which are "fixed" by the garbage collector, until what you have left is code you can't reuse without also doing garbage collection, infecting any project you bring it into.
-- Terry