If you’re drenched in the hacking and development scene, then you already know what JIT is or does. While I can’t put my finger on any specifics (because it’s stuff that – at my level of (non)expertise – goes way over my head) let’s just say that it gives you a tremendous boost of speed that Android’s never enjoyed before.
Ian Douglas, a developer at Armor Games, got his hands on a Nexus One that appears to be equipped with Android 2.2 (courtesy of none other than Adobe) and he’s pretty confident that the build of Android he’s running is equipped with a pretty stable implementation of the just-in-time compiler.
Normally, Linpack benchmarks (for which you can find an app on the market) would net him 6-7 MFLOPS on his Nexus One with stock Android 2.1 (and a bit higher with CyanogenMod versions), but the beta release of Android 2.2 he’s running pushes him close to 40 MFLOPS with operations being executed in less than 2-tenths of a second.
Astonishing, is all I can say. I use the Linpack benchmark myself on my rooted G1 with a JIT-enabled rom (HTCClay’s latest CM5-based SuperBad, for those curious) and I can tell you that – along with improved benchmark scores – it does provide some awesome real world performance enhancements in my case. Normally my G1 would huff and puff at 1.8 MFLOPS on stock Android 1.6, and around 2.2 MFLOPS with an older non-JIT-based 1.6 rom. With HTCClay’s rom with JIT enabled, I am pushing 3.5 MFLOPS average, and getting bumped up to 4.5 after an overclock to 710mhz. Even before the overclock, my G1 is running Android 2.1 noticeably faster than it’s ever run 1.0, 1.1, 1.5, or 1.6.
There’s no doubt that JIT does make a difference, and it appears Google’s embracing this (certain Google engineers are deeply rooted into the mod scene and bounces ideas off of developers like Cyanogen) and is implementing a stable version of the compiler for the Dalvik virtual machine. None of this is confirmed yet, but there will be a session specifically for JIT with Android at next week’s Google I/O conference, and hopefully we can get 100% confirmation that JIT and Android 2.2 have been married for an insanely effective performance boost on any Android handset that will run it.
[via Android Police]