Is the rebuilding of the Dalvik Cache done when the annoying “Optimizing apps” window comes?
That is easily reproducible: either by a FPOS update or by interrupting the boot process (for example, if you take out the battery while booting).
How I understand it (not that I know anything about it) is that the first time you install an app, ART creates an ELF binary for it. That takes a bit more space than before, but that’s it. At least according to Wikipedia, but maybe someone has to check the code 
At install time, ART compiles apps using the on-device dex2oat tool. This utility accepts DEX files as input and generates a compiled app executable for the target device. The utility should be able to compile all valid DEX files without difficulty. However, some post-processing tools produce invalid files that may be tolerated by Dalvik but cannot be compiled by ART. For more information, see Addressing Garbage Collection Issues.
Source, see above: Android runtime and Dalvik | Android Open Source Project
BTW: There are two ART “engines” … one is optimized by Qualcomm to generate better code for the SoC.
2 Likes
Yes, this is when all the optimizations for an App happen - both for ART and Dalvik. But it often only optimizes apps that have been updated and not the entire system.
1 Like
Hello,
I’m a Fp2-User since january, doing all the updates up to 1.51 and having rooted the phone because I want to have the permission to write to the SD-Card for all my apps.
I didn’t have major problems with the Fp2 and I would say I’m a user with some wishes for the future which are better sound of the speaker (which is really poor) and a OS on the basis of Android 6.
I am a user who can help himself in minor problems, using the forum and the internet.
Before I had a Sony xperia over many years, and I would say the Fp2 isn’t less reliable.
I would say I’m a reasonably satisfied user, a little sad that the device does not reach the quality of a high end smartphone.
1 Like
No hardware issue for my Fairphone since January, excepting some screen flickering after disassembling it and reassembling, trouble gone after some weeks.
Some software issues (FOS 1.5.1) : random loss of SIM if accurate positioning is enabled, ear-speakers too loud even at minimum volume.
1 Like
I bought four FP2’s, one for myself and three for my children who use the FP2 for private use and work (by the way: I am 79 years old). We are using the phones for about five months and have had no problems.
8 Likes
Which programmes would you recommend to test the stability of the phone? I am pretty sure my problems are caused by the updated OS not working on my particular phone, but Fairphone can’t help me until I am sure that it is a phone problem rather than an app problem…thanks!
Honestly, just normal burn in stuff and some test cases. So a) produce a high cpu load, b) run a program that needs a lot of memory, c) graphics, d) wifi, e) networks.
Google CTS test cases will check all this and FP runs those, I think. But honestly I don’t care so much, it’s FP job to get QA right and they don’t share info so it’s hard to tell.
https://source.android.com/compatibility/cts/downloads.html
https://static.googleusercontent.com/media/source.android.com/en//compatibility/android-cdd.pdf