RAM reccomendation
- Thread starter penguin055
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The 2GB reccomendation is based on?
If you have a 64bit OS and at least 4GB of physical RAM then don't worry about it. the defaults will be fine. But think about upgrading to 8GB as, with monster at least and MF3 doesn't look that muchsmaller, you can't run both chrome AND Monster AND a server without hitting the RAM ceiling.
If you have a 64bit OS and at least 4GB of physical RAM then don't worry about it. the defaults will be fine. But think about upgrading to 8GB as, with monster at least and MF3 doesn't look that muchsmaller, you can't run both chrome AND Monster AND a server without hitting the RAM ceiling.
Typically you want to only allocate half of your RAM to MC, saving the rest for tasks, other programs, wikis, etc.
Be aware that due the way java works if you add too much ram it can very easily become counter productive as its garbage collection bugs out. Basically from what I've heard it is never a good idea to go over 4gb of ram dedicated to minecraft.
Running Monster, averages at 1.5GB, and peaks at 2.2GB at very intense moments, so I tend to keep it at 2.5GB just to be safe (got 4GB total).
If I'm not mistaken, Launcher defaults at 1GB, and you WILL have problems there, with random jerkyness, overall horrible performance and a lot of "cannot keep up" messages in console.
2.5GB seems to be the sweet spot for me.
If I'm not mistaken, Launcher defaults at 1GB, and you WILL have problems there, with random jerkyness, overall horrible performance and a lot of "cannot keep up" messages in console.
2.5GB seems to be the sweet spot for me.
The RAM allocation you set in the launcher is not, I repeat, NOT the RAM allocation to Minecraft as a whole. It's the allocation of heap space, which is one out of 4-5 different memory spaces that the JVM uses to work with internally. And then there's the amount of memory the JVM uses to run itself, which is another matter entirely.
Your Windows task manager sums up all these different memory pools into one big number. So when you notice that it shows you as using 2 GB of memory in the task manager, that's a combination of heap space and eden space and young generation and permanent generation and JVM memory and god knows what else. Heap space is probably around a quarter of that total amount... maybe a third at most, unless your force Java to assign a giant heap. In that case you game will assign far more memory than it can ever use, and it will also slow itself down with trying to manage that huge space.
Most of the time you run well with 1 GB heap space assigned. If you encounter issues, up the slider to 1.5 GB. Under no circumstance should you ever put it above 2 GB because increasing the slider above what you need just lowers performance and there is no known configuration of mods that actually requires that much heap space. 99 out of 100 "out of memory" errors that modded Minecraft throws are actually the result of bugs that would happen no matter what you have assigned, or permgen space related, which is an entirely different memory space and not affected by the slider in the launcher at all.
Your Windows task manager sums up all these different memory pools into one big number. So when you notice that it shows you as using 2 GB of memory in the task manager, that's a combination of heap space and eden space and young generation and permanent generation and JVM memory and god knows what else. Heap space is probably around a quarter of that total amount... maybe a third at most, unless your force Java to assign a giant heap. In that case you game will assign far more memory than it can ever use, and it will also slow itself down with trying to manage that huge space.
Most of the time you run well with 1 GB heap space assigned. If you encounter issues, up the slider to 1.5 GB. Under no circumstance should you ever put it above 2 GB because increasing the slider above what you need just lowers performance and there is no known configuration of mods that actually requires that much heap space. 99 out of 100 "out of memory" errors that modded Minecraft throws are actually the result of bugs that would happen no matter what you have assigned, or permgen space related, which is an entirely different memory space and not affected by the slider in the launcher at all.
On that subject, Java's default permgen space of 64Mb is too small for monster and it should be upped to 128Mb - The FTB launcher ups it to 256Mb by default which is actually too much and will cause Monster to be memory starved faster on low spec machines.
Permgen space is dynamically managed up to 256MB with the launcher settings, not fixed to 256MB. A system with 2GB total RAM available will use exactly as much permgen memory with this setting as if it was using a 128MB setting.
You can confirm this for yourself using tools such a JVisualVM which graph memory usage at runtime for all of the various workspace pools.
You can confirm this for yourself using tools such a JVisualVM which graph memory usage at runtime for all of the various workspace pools.
I find the biome mods are the actual hogs when it comes to texture memory. (Looking at you EBXL / BoP).
Allthough it must be noted that texture memory is managed by OpenGL, and assigning memory to Java can (on 32bit OS's) prevent it from being used by OpenGL so thats another reason to not fiddle Javas memory allocation too high.
Allthough it must be noted that texture memory is managed by OpenGL, and assigning memory to Java can (on 32bit OS's) prevent it from being used by OpenGL so thats another reason to not fiddle Javas memory allocation too high.
Yes, with Monster and Sphax 64x (about 95% of all mods textures) I have to run at 6GB in the slider for smooth performance, it will run at 4GB but not as nice. LightHero on bdcraft runs 128x and he has to have his at 8GB or MC won't even launch.
8GB heap space? That's insane. At that level you pretty much already need to jump through hoops to avoid microstutter from garbage collection cycles...
Wonder if something in Monster has a memory leak. I mean, something besides the way vanilla Minecraft does dimension transitions.
Wonder if something in Monster has a memory leak. I mean, something besides the way vanilla Minecraft does dimension transitions.
I think it does, I can run any other pack with IRC and iTunes open with 1-2GB of free RAM, but for some reason, it got me down to like 400MB of free RAM. It was ridiculous.