5 ms·

Redex runs at compile time, not at install time.

• tananaev 10y ago
  Yes, but it changes the byte code, and I think android compiles that code into machine code when you install an app.
  • muricula 10y ago
    If anything it sounds like it would be faster because there is less byte code which needs to be compiled. Most likely the problem is the Facebook app has a lot of bytecode. That's probably why the wrote redex in the first place, so they would have less bytecode in their final APK.
    • tananaev 10y ago
      Any other app takes seconds to install. Facebook takes minutes. I can understand some difference, but not that much.
      • Lx1oG-AWb6h_ZG0 10y ago
        Their ios app has over 18000 classes (https://www.reddit.com/r/programming/comments/3h52yk/someone_discovered_that_the_facebook_ios/ https://www.reddit.com/r/programming/comments/3h52yk/someone...), so I can easily believe the android app is similarly bloated as well. (To be fair, most of the 18K classes seem to be auto generated, but that still doesn't lessen the compiler's burden.)
      • spacemanmatt 10y ago
        I heard there are something like 400 mobile developers working on the FB apps. I don't know there's any way to keep a team that size from producing bloat with every revision.
        • iainmerrick 10y ago
          That seems like a useful engineering problem for Facebook to try to solve, rather than this bullshit rocket science optimization stuff that adds yet more complexity for only incremental gains.
          • pcwalton 10y ago
            Compiler optimizations are not "bullshit rocket science optimization". You depend on them every day. None of the optimizations in this tool are "rocket science" compared to the optimizations that GCC, for example, does.
            • iainmerrick 10y ago
              Right, so on Android if you need code to be fast, write it in C++. If you have a ridiculously bloated and buggy Java app, writing an optimizing compiler doesn't sound like the most effective solution.
              • spacemanmatt 10y ago
                My take: If you can't write it fast enough in Java, it is probably not a good mobile app candidate in the first place. The Dalvik optimizer and the JIT yield a regularly reasonable experience for me.
      • karlding 10y ago
        There was a post on HN [0] a few years back about the Dalvik patch that Facebook used for their Android app, due to the large number of methods [1] the app had. This was causing issues on the older Gingerbread devices, so their solution was to modify the internals of the Dalvik VM while it was running their code to increase the buffer size. [0] https://news.ycombinator.com/item?id=5321634 https://news.ycombinator.com/item?id=5321634 [1] https://www.facebook.com/notes/facebook-engineering/under-the-hood-dalvik-patch-for-facebook-for-android/10151345597798920/ https://www.facebook.com/notes/facebook-engineering/under-th...
        • V-2 10y ago
          Which is borderline insane
  • timdorr 10y ago
    That is actually going away in Android N: http://developer.android.com/preview/api-overview.html#quick_path_to_app_install http://developer.android.com/preview/api-overview.html#quick...