How to allocate to Mac and Windows

Discussion in 'General Questions' started by ez22, May 21, 2007.

  1. I'm new to all this. Can someone please tell me how to allocate hard drive space or memory or whatever it is to the two different operating systems on the MacBook Pro? I just heard about doing this and haven't got a clue where to begin. Thanks
  2. It depends.

    If you are installing Parallels only, you can let the installation program set defaults for all that stuff and it works well. You will probably get an 8GB virtual hard disk. If you are going to be storing mass quantities of large files on the windows side, you can increase the 8GB in the custom install options. I would take their recommended defaults for the memory.

    If you are also installing bootcamp, it gets more complicated, and since I don't have bootcamp, I wont comment on that.
  3. It seems common for folks new to virtualization to stumble over memory allocation. That's a key contributor to performance problems. Both OS X and Windows love RAM. If either is starved for it, they create 'fake RAM' using the file system (a.k.a. virtual memory). Since both host & guest OSs often reside on the same physical disk in a virtualization scenario, one OS hitting virtual memory too often will affect the performance of both OSs. This is because only one OS can access the disk at a time and disk I/O is about 1000x slower than memory access.

    The solution is to have enough RAM to feed both OSs. Personally, I don't recommend virtualization on a machine with less than 2 GB of physical RAM. I guess 1.5 GB would be fine, too, but that's not a typical configuration. I know that others here may disagree. I'm just going on what I've learned using virtualized environments over the years. You can get away with less if both OSs are optimized and/or if the virtualized OS only runs a critical app or two.

    As a rule of thumb, when running XP under Parallels on a Mac w/2 GB of RAM, XP should be happy with 512 - 768 MB allocated to it.
  4. Allocating to Mac and XP

    I really appreciate all your responses to my question. I have 3 GB of RAM on the MacBook Pro. It sounds like the defaults will work fine. I haven't had any problems yet, though I am mostly running the Mac side. For future reference, is it reasonably straight forward? Anyone know how to do it? Thanks again.
  5. Sounds like you're nicely set for RAM. If the defaults are working for you then you're good to go. One suggestion: if Parallels has defaulted to less than 512 MB, you may want to manually boost it to 512 MB and see if you notice a difference. You certainly would seem to have plenty of RAM left over for OS X.
  6. That's what I'm asking ! HOW do you do that?



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