Hi Erik, sorry for the delay ... > I'm not a *nix guru, though I can follow guides and the basic concepts. With me too :-) ...
Just for info, are you using the RPi with 256 or 512 MB of RAM ? What model ? > that in mind, the only way I've figured out how to view a Pivot app on the > RPi is to see the graphics output from within the window manager (LXDM, > after calling 'startx'). This means doing startx, then either going to > another tty via, say, ctrl-alt-f2, or opening the run dialog in LXDM via > alt-f2. From there, I call a script that launches the Pivot app. If in tty, > I go back to the window manager via ctrl-alt-f7. My current script, as an > example, can be found here: > > https://gist.github.com/einnocent/6207649 all seems ok, if you could open a Terminal/Console directly inside the window manager it could be a little (but only little, I know) better ... if you can, try to use less dependencies. On o different PC, try to attach to the running Java process in the RPi from remote, using JConsole or better, JVisualVM (bundled in all Java 7 JDKs). > So the good news is that Pivot runs on the RPi. great, thanks for reporting to us > The bad news? Things are unusably slow. I really think (as many others over Internet) that it's probably due to the little memory (and poor CPU processing power) of RPi, so any Java GUI application on it won't be fast ... maybe with some modularization of JRE (with Java 8 or 9 ?) things should be better > I'm doing mostly scaling and placement of SVGs within a > panel, with maybe a dozen labels, so I'm guessing it's not my app doing > anything crazy intensive. (Or am I wrong?) try to not use SVG images, and even use small images if you can ... Last, try if without using bxml files (setup GUI directly in code), if something is better (but I don't thing this should reduce memory footprint a lot) ... > I've a few ideas for speeding things up, namely: > > Using JRE8 instead of JDK8. I don't expect this to yield big gains and can't > wait for the official release of Java 8 next year > (http://openjdk.java.net/projects/jdk8/). I agree with you > Using a faster memory card. I also don't expect much from this as I'm not > doing much disk operation and I don't think I'm swapping out to the SD a faster memory card could help, but try to check if/how much swap you are using (and where the OS is writing the swap), and (if possible) try to disable it (temporary), but attention !! > Using a faster computer, using Windows. More expensive and less elegant I know, but of course with limited hardware (and Java memory footprint) RPi is not well suited for some kind of applications ... and Windows has always been the de facto standard for GUI applications > Using a faster computer, using Linux. More expensive and I could have similar > issues no, we have many users under Linux, here all is good ... otherwise Java wouldn't make sense for us > Using JavaFX. I'd have to learn another framework, but then I could avoid X, > which I think is what's slowing things down (I think the graphics are being > handled by the CPU instead of the GPU). I don't know if JavaFX takes > advantage of the GPU, but the dedicated link here > (http://www.oracle.com/technetwork/java/javafx/overview/index.html) seems to > indicate some level of support. yes, JavaFX uses GPU, but for whet I know, you always need X under, so things should be the same even there. I think that they use a lot Python (and some graphic library/GUI) for it, this should require less memory than Java. > Using Weston/Wayland (http://wayland.freedesktop.org/raspberrypi.html). > Getting Wayland running on the RPi has been a pain and I'm still not there > yet. I'm guessing it will be built into an upcoming release of Raspian, but > I can't wait for that. I also worry if it will even help, since the app will > be going through XWayland (http://wayland.freedesktop.org/xserver.html). but is/will it be compatible with X ? and with Java ? could be interesting ... > Using pivot-fx? I'd like to try this but the project > (https://code.google.com/a/apache-extras.org/p/pivot-fx/) appears to be > dormant. Anyone know what's going on with this? I created that project many time ago, but due to lack of interest it's still empty ... > So, does anyone have any suggestions on how to speed things up? Any input on > my ideas? And does anyone know what's going on with pivot-fx? I'd really > like to get a Pivot app running on the RPi, I think it would be really cool =) I hope my previous answers could give you some info ... if you need more, tell to us > Thank you so much for your help! thanks to you for your help, I hope we can improve Pivot on RPi (and other minimal platforms) ... Anyway, tell us for news. Bye, Sandro
