I'm having Java issues.

I am not sure if either Java is not working exactly as it should on my system, or if I'm just a complete noob and am doing something completely wrong somewhere.
I am trying to set Java so that it will have both a minimum and a maximum of 1000 megabytes for heap space. I've done this by going into the Java section of my Windows XP control panel, clicking on the Java tab, and then in the runtime parameters for every version of Java that I have, since I'm not sure what version Forge is using, I've entered -Xms1000m -Xmx1000m. My thinking is that when I take look at Task Manager, I should be seeing javaw.exe using 1000000 K of memory, but I've never seen it use more than about 315000 K of memory. How do I make sure that Java is using the memory that it should so that I can run Forge for more than 3 matches in a row without my system completely bogging down?
Edit: I'm looking at VisualVM, and it shows that my heap is still right around 256 MB in size. For some reason, Java is completely ignoring my command to increase the heap size to 1000 MB. I really need to know how to ensure that Java accepts my heap size commands.
Edit2: I'm about ready to throw up my hands in disgust and go back to an earlier version of this game from back before this whole heap space problem started for me. I am simply unable to get Java to change the heap size that Forge is using. No matter what I do to change it, the heap size according to VisualVM is always 266ish million bytes. I've tried to bing search ways to change it and none of them seem to make a damned bit of difference. Or, could someone answer a question: Is it possible to run an already fully compiled beta release through Eclipse, since it seems that it might be easier to actually get heap size changes to stick using that?
Edit3: I've downloaded Eclipse and Subclipse and am running Forge from inside of that. Even with changing eclipse.ini to have -Xms1000m -Xmx1000, running GUI_NewGame results in Forge only getting a heap of 266338304 bytes. I did a text search within the project, and I discovered a few instances of -Xmx1024m, however, I'm not sure that that is ever being reached. I'm thinking that perhaps there needs to be -Xms1000m parameters entered into the code at the appropriate places as well.
I am trying to set Java so that it will have both a minimum and a maximum of 1000 megabytes for heap space. I've done this by going into the Java section of my Windows XP control panel, clicking on the Java tab, and then in the runtime parameters for every version of Java that I have, since I'm not sure what version Forge is using, I've entered -Xms1000m -Xmx1000m. My thinking is that when I take look at Task Manager, I should be seeing javaw.exe using 1000000 K of memory, but I've never seen it use more than about 315000 K of memory. How do I make sure that Java is using the memory that it should so that I can run Forge for more than 3 matches in a row without my system completely bogging down?
Edit: I'm looking at VisualVM, and it shows that my heap is still right around 256 MB in size. For some reason, Java is completely ignoring my command to increase the heap size to 1000 MB. I really need to know how to ensure that Java accepts my heap size commands.
Edit2: I'm about ready to throw up my hands in disgust and go back to an earlier version of this game from back before this whole heap space problem started for me. I am simply unable to get Java to change the heap size that Forge is using. No matter what I do to change it, the heap size according to VisualVM is always 266ish million bytes. I've tried to bing search ways to change it and none of them seem to make a damned bit of difference. Or, could someone answer a question: Is it possible to run an already fully compiled beta release through Eclipse, since it seems that it might be easier to actually get heap size changes to stick using that?
Edit3: I've downloaded Eclipse and Subclipse and am running Forge from inside of that. Even with changing eclipse.ini to have -Xms1000m -Xmx1000, running GUI_NewGame results in Forge only getting a heap of 266338304 bytes. I did a text search within the project, and I discovered a few instances of -Xmx1024m, however, I'm not sure that that is ever being reached. I'm thinking that perhaps there needs to be -Xms1000m parameters entered into the code at the appropriate places as well.