JDK-6749176 : Standard heap memory size (of Applets) too low
  • Type: Enhancement
  • Component: deploy
  • Sub-Component: plugin
  • Affected Version: 6u10
  • Priority: P4
  • Status: Closed
  • Resolution: Won't Fix
  • OS: windows_xp
  • CPU: x86
  • Submitted: 2008-09-16
  • Updated: 2010-04-04
  • Resolved: 2008-09-17
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Description
A DESCRIPTION OF THE REQUEST :
If running applets you can not allocate arrays with a length greater of ca. 55 MB due to the 64 MB limit of the heap memory in standard config (which is not changeable from the applet programmer). This violates the backward compliancy to Java 1 Machines (Microsoft Java Machine)  of the year 1999.


JUSTIFICATION :
Multimedia webapplets with preloading of longer media sources dont' work with the Java Version 1.6.10. Instead they work with a Java Machine of 1999 (Microsoft Java Machine)

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Java Applets running the current Java Version 1.6.10, which are able to preload sources with a higher size of 64 MB, so that the applets works like on 10 yeart old Microsoft Java Machines.
ACTUAL -
Java Applets running the current Java Version 1.6.10 aren't able to preload sources with a higher size of 64 MB due to an antique heapsize memory size value.

---------- BEGIN SOURCE ----------
// Insert following code into an applet
.........................
int[] test;

test = new int [65000000];
.....................
---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
No found

Comments
EVALUATION Previous versions of the Java Plug-In contained grotesque hacks to silently increase the Java heap size on machines with more than a certain amount of RAM. These hacks were specific to the Windows operating system and there was no specification of their behavior. The new Java Plug-In has a radically different architecture which provides applets much more control. Complex applets can specify a per-applet heap size using the java_arguments parameter. For example: <param name="java_arguments" value="-Xmx128m"> This functionality is documented in the new Java Plug-In's release notes at https://jdk6.dev.java.net/plugin2/#COMMAND_LINE_ARGS . Ideally it would not be necessary to specify -Xmx, but realistically doing so will probably be necessary for some time. The new Java Plug-In provides a straightforward general solution for the applet developer. We have not observed significant compatibility issues due to the change of the default heap size in extensive testing with applet content from throughout the Internet. It is imperative that we move toward a simpler and more unified applet infrastructure. For this reason, we will not be adding back in the complex and Windows-specific heuristics from the old Java Plug-In. Closing as "Will Not Fix".
17-09-2008