Java-Gaming.org Hi !
Featured games (83)
games approved by the League of Dukes
Games in Showcase (539)
Games in Android Showcase (132)
games submitted by our members
Games in WIP (603)
games currently in development
News: Read the Java Gaming Resources, or peek at the official Java tutorials
 
    Home     Help   Search   Login   Register   
Pages: [1]
  ignore  |  Print  
  why does my memory usage spike up and down  (Read 3159 times)
0 Members and 1 Guest are viewing this topic.
Offline Quadro

Senior Newbie





« Posted 2012-09-10 00:30:59 »


when I run other people programs they seem to have a steady and smooth movement not spike up drop spike up drop, also why would the heap size be so big if the used heap is much lower, it's a 2D platformer game so could it be too many threads or objects
Online Riven
« League of Dukes »

« JGO Overlord »


Medals: 841
Projects: 4
Exp: 16 years


Hand over your head.


« Reply #1 - Posted 2012-09-10 00:33:33 »

Because your program has spikes in memory allocation, after which the GC kicks in, cleaning up the garbage.

There's nothing else to say really. Look at your code to find the cause.

Hi, appreciate more people! Σ ♥ = ¾
Learn how to award medals... and work your way up the social
Offline ReBirth
« Reply #2 - Posted 2012-09-10 00:39:54 »

Maybe you periodically create new object(s)? well, as long it doesn't affect your game in play time don't mind it too much.

Games published by our own members! Check 'em out!
Legends of Yore - The Casual Retro Roguelike
Offline sproingie

JGO Kernel


Medals: 202



« Reply #3 - Posted 2012-09-10 00:48:32 »

Since it looks like your spikes are followed by an immediate GC, your allocation spike is likely happening in one place.  If you enable GC logging (see here for an example of how) and add some debug logging to various bits of your program, that can help in tracking down the culprit by matching up the debug log timestamps with the GC log.

Since it's very short-lived garbage, another alternative is to just live with it, since collecting it should be plenty fast.  That's a less palatable option on Android though.
Offline princec

« JGO Spiffy Duke »


Medals: 434
Projects: 3
Exp: 16 years


Eh? Who? What? ... Me?


« Reply #4 - Posted 2012-09-10 09:04:24 »

Also your max heap size looks rather excessive versus your needs there. I'd set it to maybe 260mb and see how it goes.

Cas Smiley

Offline i30817

Junior Devvie





« Reply #5 - Posted 2012-09-13 09:48:38 »

You're probably creating a large temporary array.
Offline Damocles
« Reply #6 - Posted 2012-09-13 11:22:20 »

A typical memory waster is to build Text out of concanated Strings.
like :  message = message + " is " + "here";

As each time a new String Object is created.

Try using a StringBuffer here.

Offline Best Username Ever

Junior Devvie





« Reply #7 - Posted 2012-09-13 14:21:50 »

A typical memory waster is to build Text out of concanated Strings.
like :  message = message + " is " + "here";

As each time a new String Object is created.

Try using a StringBuffer here.

The compiler already does that. One new String is created.
Offline Damocles
« Reply #8 - Posted 2012-09-13 14:33:24 »

Yes its one new String object.
I ment the whole instruction with "each time".
When used each frame for example.

Opposite to a StringBuffer where you can append a String without creating a new object.

Offline DrHalfway
« Reply #9 - Posted 2012-09-13 14:40:19 »

I'm on the same boat Quadro, one thing i've learnt is to run memory analyzers as you develop the software to catch these sort of things, also if you use external libraries i'd check those too, make sure they aren't the ones causing the garbage collector to go haywire.

If you're developing a game, you can probably come up with a scheme to reuse most frequently used objects. On modern java, the GC's are pretty optimal and on a PC platform it wouldn't matter too much, i'd only start worrying if you were deploying for Android. Then again, reuse has never been anyone's enemy, plenty of pooling tutorials available.

Pages: [1]
  ignore  |  Print  
 
 
You cannot reply to this message, because it is very, very old.

 

Add your game by posting it in the WIP section,
or publish it in Showcase.

The first screenshot will be displayed as a thumbnail.

rwatson462 (36 views)
2014-12-15 09:26:44

Mr.CodeIt (29 views)
2014-12-14 19:50:38

BurntPizza (61 views)
2014-12-09 22:41:13

BurntPizza (98 views)
2014-12-08 04:46:31

JscottyBieshaar (58 views)
2014-12-05 12:39:02

SHC (74 views)
2014-12-03 16:27:13

CopyableCougar4 (76 views)
2014-11-29 21:32:03

toopeicgaming1999 (137 views)
2014-11-26 15:22:04

toopeicgaming1999 (127 views)
2014-11-26 15:20:36

toopeicgaming1999 (37 views)
2014-11-26 15:20:08
Resources for WIP games
by kpars
2014-12-18 10:26:14

Understanding relations between setOrigin, setScale and setPosition in libGdx
by mbabuskov
2014-10-09 22:35:00

Definite guide to supporting multiple device resolutions on Android (2014)
by mbabuskov
2014-10-02 22:36:02

List of Learning Resources
by Longor1996
2014-08-16 10:40:00

List of Learning Resources
by SilverTiger
2014-08-05 19:33:27

Resources for WIP games
by CogWheelz
2014-08-01 16:20:17

Resources for WIP games
by CogWheelz
2014-08-01 16:19:50

List of Learning Resources
by SilverTiger
2014-07-31 16:29:50
java-gaming.org is not responsible for the content posted by its members, including references to external websites, and other references that may or may not have a relation with our primarily gaming and game production oriented community. inquiries and complaints can be sent via email to the info‑account of the company managing the website of java‑gaming.org
Powered by MySQL Powered by PHP Powered by SMF 1.1.18 | SMF © 2013, Simple Machines | Managed by Enhanced Four Valid XHTML 1.0! Valid CSS!