I always get java.lang.OutOfMemoryError: Java heap space error when I try to run any J2ME program in Netbeans (with the big green play icon). How can it be fixed? (I can run J2ME programs after I build them in netbeans and double-click on the generated JAD file.)
Try increaing the allowed heap space
Check Tuning JVM switches for performance
There is a good thread for tuning eclipse: What are the best JVM settings for Eclipse 3.4?
Some of that may be useful to you
Related
Android Studio uses 100% CPU when I'm just coding, even if I type a single word CPU use raises to the 100% and comes to back normal, and if I keep typing it takes 100% CPU all the time.
What I have tried is :
File > Invalidate cache and Restart
Change max heap size for android studio by editing VM options
"Power Save Mode" it runs perfectly when it is turned on. but it also disables some useful features of IDE and I don't want to disable it.
removed .android and .AndroidStudio3.0 folder from c:\users\username\
Android Studio plugins are set to default. no extra plugins are added. I tried disabling a plugin that can be disabled like Git and SVN but it's still same
I'm running windows 7 64-bit OS and Android Studio 3.0 and OS which I re-installed yesterday. I did not install the JDK - Android Studio is using default OpenJDK.
I've searched on internet but it did not help. any help would be appreciated.
Unfortunately, the new Android studio do require RAM.
"
You can download Android Studio 1.5.2 which should support 2Gbs of Ram And I would also recommend you to move to Linux Ubuntu OS from Windows 10 as you can set a portion of your Hard disk space as Ram memory(4gbs recommended) during installation(Search on Youtube on how to do that)."
Source quora:
It seems your systems config is low. as Android studio cares of itself for CPU uses so it gives its best.
Reasons being
You have Core 2 duo that is too low for Android Studio.
You have 4gb Ram, that is too low again.
If you work on some large project then 2gb of ram is necessary for Android Studio. and Java takes unexpected upto 4gb or more.
Solution
Increase ram by 8gb and processor at least intel i3
kill java or invalidate cache and restart if you get stuck of hanging your android studio.
Here is my CPU uses that goes upto 3gb for Android Studio and upto 4gb for Java.
The recommended hardware requirements for Android Studio are:
Microsoft® Windows® 8/7/Vista (64-bit Recommended)
Intel i5 4th-5th gen processor.
6 GB RAM
2 GB hard disk space + at least 1 GB for Android SDK, emulator system images, and caches
Optional for accelerated emulator: Intel® processor with support for Intel® VT-x,
As Java uses it’s own Machine known as JVM(Java Virtual Machine) for program compilation and it has some complex tasks like generate classes then verify byte code and then execute program with JIT(Just In Time)
And as Android has Natively developed in Java the slow compilation will be the issue i presume. But with new Android Studio feature known as “Instant Run” compilation and development of Android apps made more easy.
As i am developer of Android apps, I use
Intel i5 6th gen 2.70 Ghz processor
12 GB of RAM (8GB in first slot and 4 in Second Both DDR3)
1 TB of Hard Drive
Nvidia G-Force 940M 2 GB of Dedicated GPU for running Adobe After-Effects, Maya and Unity like Software which needs Dedicated GPU.
That’s all and Still Android Studio sometimes Lags with such high performance Hardware with the more complex and big apps(Complex Projects).
I think if you are going to buy a hardware and use it for at-least 3 years get the exact specs i have (or similar), However if you are frequent hardware changer use specs i mentioned first.
And for Emulator use Genymotion as it is way faster then the emulator which Android provides. Or use some other alternatives like Memu, Blustacks, Andy etc.
Try to add more Heap memory for Android Studio, go to Help -> Edit Custom VM Options... and set -Xmx2g (depends on your project size), after restart AS.
Did you try to set the power plan to best performance instead of balanced plan.
This may consume the battery but may solve this problem.
If you have any USB drives laying around, try using those for ReadyBoost. It may help you.
For the uninitiated, ReadyBoost, in a nutshell supposedly makes your WINDOWS PC faster by using how much ever space you dedicate it to (aka extra RAM)
For the uninitiated, to set it up,
Plug your USB / SD /WHAT EVER DIGITAL STORAGE you have into your computer
Go into Windows Explorer > This PC > Right click on Whatever storage you have plugged in
Select Properties in the Context (right click) menu
Go to the ReadyBoost tab
Choose what to do with it
Go to: Preferences > Version Control > Background. Now listed under 'Background Operations' are 6 options. I disabled the first three options which are:
Perform update on VCS in background, Perform commit to VCS in background, Perform checkout to VCS in background.
This reduces lot of power consumption of the CPU
I am aware that Hotspot JDK7 has both Java Mission Control and flight recording bundled with it. But, as per my application requirement, I am bound to use Hotspot JDK6. I could monitor the Hotspot6 JVM performance using JMC. But flight recording is disabled for Hotspot6 JVM. Is there any other tool equivalent to it for Hotspot6?
Nothing equivalent, but you can try jconsole or jvisualvm (in the bin directory).
I built a game in j2me and I have memory leak because from time to time I get out of memory exception, now I want to spot where this leak is coming from and I heard you can do it with sun's wireless tool kit. Can someone explain me exactly what is this wireless tool kit, how I install it and how to use it in-order to find memory leaks ? Thanks in advance !
After you download wtk,Go to \bin\utilsw.exe.Under Utilities you will see "Memory monitor".Here you can graphically view app memory/RAM usage.
I do not know oracle sdk 3.4, but in wtk2 memory monitor was only partially useful for finding memory leaks, because it only shows how many (and which) objects are live, but not where they are referenced from. So it takes a review of corresponding piece of code.
Memory leaks are easier to find with a java profiler. You need to get one that suits you (I prefer YourKit, but it is commercial product with a trial period), modify emulator's command line in order to allow the profiler to connect (that should be covered by profiler's documentation, it is basically about adding -agentlib or -Xrun... option) to it, and do actual profiling (every profiler comes with a guide of how to do it).
As an Android developer I've been moving away from Eclipse to Intellij IDEA for production code in anticipation of Google's Android studios which shares a code base with IDEA.
My experience has been a good one up to this point. I've only been using IDEA at the office, where I have a 4x core Intel i7 machine running Ubuntu 12.04 LTS (Sun JDK/JRE), up to this point and I've never noticed what the performance of IDEA really is.
Now however after setting IDEA up on my personal computer at home the performance is abysmal. Memory usage is normal, but the constant CPU usage bounces between 80%-100% (over the whole application lifecycle). And that is when nothing else is running on the machine and no work is being done, by me or visually by the IDE.
This makes IDEA unusable when working on it, and I can forget about having anything else running along side it.
My home specs and software are:
Intel Core 2 duo 3GHz
8 GB RAM
Ubuntu 12.04 x64 LTS (3.8.0-35-generic) running of SSD SATA
Intellij IDEA 13.0-0ubuntu1 build: IC-133.193
Tried both OpenJDK and Sun
And the strange thing is that this happens as well with Android Studios.
All help in trying to debug this behaviour would be appreciated.
#Edit 1:
Noticed that the CPU load falls down to 20% when bringing up dialogs (Project structure, Settings, etc) and then goes right back up when dismissing them.
#Edit 2:
I tested simply getting the tarball straight from JetBrains, instead of using the one in Canonical's ppa. The performance was significantly better for at least an hour (20-30% CPU usage while idle). Seems that the native file watcher in C-PPA wasn't working properly and was indexing the whole filesystem.
However the performance became worse after the first hour or so, going back to 90-100% CPU.
The issue turned out to be the native-file watcher being out-of-date. IntelliJ was re indexing my whole drive it seems. Was fixed by uninstalling the version gotten from Canonical's ppa and installing directly from JetBrain's own webpage.
Are you using any plugins outside of the included ones which might cause issues.
I don't run Ubuntu anymore but can't recall any issues with high CPU-usage when i did. (I use Fedora with KDE a colleague uses Fedora with GNOME though. )
Does this always happen or only when you have a project open?
I'm thinking if this might have something to do with the background-compile that IDEA does.
Might be worth trying to turn this off.
Found under Project Settings -> Compiler -> Make Project Automatically
worst case it is a Unity-integration issue or something. Haven't used unity so can't say.
Usualy I manage to fix it by deleting IDE's index files rm -rf ~/.RubyMine60/system,
don't forget to change .RubyMine60 to IDEA's config folder
If you're willing to do some sleuthing, you could run the Oracle JVM and use the VisualVM profiler to see where the IDE is spending all its time, presuming it's a Java-based process that's actually eating your CPU cycles.
I will be running my applet on almost all the browsers for nearly minimum of 14hrs will that cause the browser to crash or hang.My applet will basiclly upload a file to remote server via ftp.
My applet size is about 1.5mb.
Best Regards,
Sagar
There's no reason the Applet or the browser should crash if your Applet doesn't allocate too much memory. Standard Java heap size is 64Mb so its quite comfortable. Moreover, your application seems to be streaming content and should not retain it in the memory. As for the size of the Applet itself, 1.5Mb is totally OK.
That being said, I would recommend going to a webstart application instead of Applets, because, well, I've had too many problems with Applets. Plugins installations, security constraints, etc... I try to avoid this technology whenever possible.