[Galaxy Y GT-S5360 General] -CALIBAN666-:
By a boot of the Android OS itself looks the Dalvik (Virtual Machine) installed applications (. APKs.) Framework and files of the corresponding ROMs and builds a tree of their dependencies to the "framework" files. On this basis, the Dalvik optimized the code of applications and stores them in the Dalvik cache. (. dex). So 2 steps only tree, "unpack" and then optimize the information contained in applications. Dex files.

In ODEX-based ROMS (usually only the original Google ROMS) these optimizations are partially done already. "ODEX" files, it is split, the application sends and contained usually in the application. Dex file already is optimized apk beside the. Itself stored (. ODEX). But since this is more difficult to change, such as themes, etc, most of the FW / ROMS are not "odex'et", but "de-odexted", so really, the optimization undone. This does not affect the speed of the ROM itself, only on the first reboot this will take longer due to take the dalvik-cache these works must.

HOWEVER! the dalvik to be working in the current system (otherwise it would not be possible to install applications without a reboot of the reason stems from a myth:... Davilk works ONLY at Start-Up That is incorrect Thus: Once, either before boot, or anything in the current system (whether changes install, uninstall or deleted apps from the Dalvik is optimized and active / the respective. index deletes files in the cache.

The cache of dalvik "sits" in the User-partion of the OS (/ data). One exception is the "Memhack" This moves the Dalvik cache to the SD card to free up space in ROM memory shortage (we were only on some older phones still used as far as I know). I'm therefore "memhack" not work here.

So if you load a new Rome (for the Milestone: by flashing a "full" releases) or manually / data partion deletes (wipes) (PS: Wipe data and factory reset are 100% the same), then this cache completely removed (as part of the / data partition). Once the ROM is then booted the dalvik resumes his work, opens his Tree of dependencies, the optimized bytecode and backs it down a new dalvik cache under the previously deleted one and now newly created / data partition.

Optimize this always happens after every reboot! Manual intervention is actually NEVER necessary, because even if there are errors, they will be adjusted automatically by the dalvik, wrong. Dex files deleted etc etc.

Examples of myth:

- I wipe / data -> cache and all data gone

- I'm playing on a new ROM (full sbf) -> cache and off all data again

- I'll wait until the flash is completed, then I reboot and go into the recovery to the (delete dalvik for 3rd time I delete a data set does not exist yet.

These 3 actions to make 3 times the same.Weird,would think as a rookie, right? Correct, absolutely free of meaning and sense.

Therefore ...

- Every reboot the Dalvik cache is optimized. It is not present (our 3 examples), it is completely created (boot time is very long when the cache is created from scratch)

- In the current system works the dalvik and keeps the OS in optimal condition

- Even IF it should ever give errors (let's say I delete an APK in the recovery, or via update.zip or other (ie where all the dalvik is NOT active in the system), which takes place next reboot, and the optimized dalvik the system again without the necessity of Wiping the caches

Question:

does wiping harms the caches? No harm,he does not. But he does bring anything (except for special cases absolute). I have installed 100 determines Flashes behind me on the milestone, and certainly the 100 Nighltlies and ROMS on the Nexus. Not even I have deleted the cache or delete anything. The Android OS takes over completely without user intervention (except for absolute special cases that give its sometimes, but I have not even seen)

ITS NOT FROM ME,I HAVE ONLY TRANSLATED WITH GOOGLE!!!!

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