Applet can take more than 600m, -Xmx256m has set ? [SOLVED]

Newbie & Debugging Questions
#1

Hello,

I have my applet " http://temp4322.dy.fi/AsiakasOhjelma.html ",
when i keep my applet running the memory of JAVA program rises 1m a second to well over 600m, i dont understand why this is possible as i have set my -Xmx256m to 256m ?

Why applet takes more memory what is set, i also has System.gc () at some points of my code, but it wont release the memory what Linux Mint 11 wants for JAVA, have i miss understood the -Xmx option ?

#2

couls you just post your whole VM arguments string, all those parameters ?

maybe you just spelled soemthing wrong, and in that case it doesn’t work.
And if I don’t set the memory in my apps, the System outputs wrong memory numbers which are very high, its all screwed up then

#3

here,

The Linux tag,

<div style="position:absolute;top:1%;left:1%;width:98%;height:97%;">
<applet code="main.Main"
codebase="http://bittipankki001.com/AsiakasOhjelma/"
archive="AsiakasOhjelma.jar"
width="100%"
height="100%">
<param name="separate_jvm" value="true">
<param name="java_arguments" value="-Xms32m -Xmx256m -Dsun.java2d.d3d=false -Dsun.java2d.opengl=true -Djnlp.packEnabled=true">
</applet>
</div>
#4

Have you looked at your program, while it is running, with a profiler? JVisualVM.exe comes with Java and is quite good for tracking down memory leaks. It can be found in the JDK/bin folder.

#5

arguments string, seems fine

point is, even with memory leaks, a java program with max 256M should get a OutOfMemoryError way before 600M

I don’t really work with applets though…

#6

That’s just the Java heap it limits. The rest of the memory is “native” heap, stack, JVM itself, any mapped files, and direct bytebuffers, of which there are probably quite a few. And it might not all be physical RAM anyway, some of it’s likely to be virtual.

Cas :slight_smile:

#7

Direct ByteBuffers,

I had the following line of code at my nio code, i had it nulled later, and at the start of my method it was installed again, i had forget it to inside a method, it is now on global area, it made my VM to collect garbage a bit less than 1M a second, sometimes it stopped the garbage collection, but started again later, i noticed the problem when my memory was running out, my VM still takes a small rise on memory requirements at times, but it is not that heavy problem anymore, my JAVA seems to take a some what a 109m currently, i keep my program running next nigth and check again tomorrow, thanks for pointing me this bytebuffer, i would not had found this line alone, thanks …

ByteBuffer buf = ByteBuffer.allocateDirect ( 2048 ) ;
#8

Yes, direct bytebuffers are meant to be used in specific ways. Generally you allocate one and expect it to remain allocated for a long long time.

Cas :slight_smile: