[Guide] How to Allocate More Memory for Java (Windows + Mac)

This guide will show you how to allocate more memory for Java, hopefully making your Minecraft run faster. For those that didn't know Minecraft runs on Java.

Windows:

Now for those people on Windows 8, Vista, and XP once you open up the control panel it should be that same steps for you. How to open up the control panel:

Windows 8:

1. With a mouse, right-click anywhere on the Start screen and then click All apps.

2. On the Apps screen, swipe or scroll to the right and find the Windows System category.

3. Press or click on the Control Panel icon under Windows System.

4. Windows 8 will switch to the Desktop and open the Control Panel.

Windows Vista:

Windows XP:

Now onto the guide!

Step 1:

Open the Control Panel:

Step 2:

Type 'Java' inside the 'Search Control Panel' box.

Step 3:

Click the Java icon that pops up.

Step 4:

Click the Java tab.

Step 5:

Click view...

Step 6:

Assure there is only ONE line in here, any more lines could cause issues.
If you have multiple lines uninstall all versions of Java from your system and download Java JDK 7 from the following link. Make sure to get the x64 version if you have a 64-bit OS.
http://jdk7.java.net/download.html

Step 7:

Change Runtime Parameters.

Put '-XmxHOWMUCHRAMYOUWANTTOALLOCATEm'

Change it depending on how much RAM you have, it is recommend you use 256/512/768/1024/1536/2048.

For 32-bit Operating Systems 768M is recommended.

If you have 64-bit, or that doesn't work, continue to try the following

1G

1536M

2G

As I said, this varies depending on how much System RAM you have.

Mac:

Now I don't own a Mac and I probably never will so I found this video to help:

Comments, complaints, concerns?

Great Guide

Very nice guide, Thanks Bob ^_^

It always seems to be... Ugh...

Thank you!

Just curious as to why you say allocate 'More memory' to java, yet you reduce it from 1024MB by default to 800MB

Just an example, it is not what I have it set to as of this moment.

I would suggest changing it to a number that is a binary factor - 256/512/768/1024/1536/2048 - Setting it to 800MB will cause errors.

I always allocate ram using G instead of M after the amount, so its in gb and not mb. So instead of 2048m, you can do 2G.

You could also do that.

Doesn't show runtime parameters. Is it because I have Java 32-bit?

It should show the runtime parameters. I am also running Wkndows 32bit and Java 32bit. Do you have the latest Java update?

Yes.

it didn't work for me, ion minecraft it still says that I only have 455MB where as I typed 2048MB into the Java thing, is it because i'm using Windows 7? I don't think that should matter but it's the only thing that I can think of, please help

Mother of bumps...

Stickied threads can be bumped.

Not stickied?

http://empireminecraft.com/forums/general-minecraft-discussion.18/

I'm pretty sure this was a sticky before...

just go to sleep.