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I've ordered a new Macbook Pro that'll come pre-installed with OS X Lion (500 GB HDD). For someone like me who's always heard and watched, but never actually worked on a Mac, this is gonna be a completely new experience.

Windows 7 will continue to be a big part of my work and I plan to first install it via Bootcamp and then eventually get that bootcamped-partition on Mac OS X interface via VMWare or Parallels. My current confusion is related to the partitioning of the new system and how it is different from what I used to do in Windows.

I have been doing a lot of research on this and have almost got a hang of using boot camp to set up Windows 7. What I am not able to understand is whether I should create a new data partition like I used to do in Windows.. you know to protect my data in case the main OS install goes for a toss.

I came across this thread on Macworld forums which has both pro and counter arguments against creating a third data partition on Lion. If you take a quick look and scroll to the very bottom, you'll see that user there says, "having a Data partition in no way shape or form .... protects anything... secures anything.... makes it easier... or benefits anything." he correct? I mean, doesn't separating data from the OS install in Mac make sense like it does in Windows??

I'd also appreciate any other partioning related tips and suggestions on using Windows+Mac together productively on a Macbook Pro with Lion.

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No need to repartition. It works well with one partition just make sure it does not go >90% full and fragmented.

You have quotas, virtualisation and other goodies to not use bootcamp and repartition with expensive tools.

I am repeating myself probably - but filling OSX partition once in a lifetime will make it badly fragmented and slow for the rest of it's life. Obvioulsy 8GB C: drive is not needed for hardware compatibility, and such small drive is more likely to grow fulll and get slow.

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No, I understand what you are saying. What I am really concerned about is data security in an unlikely case of an operating system failure. See my reply to the answer above. That's what I am trying to figure. I am not sure how it works in Mac but in Windows, even if I couldn't boot into C: due to an OS error, I could always access the G: drive or any other partition through various means and extract the data. – abhim12 Feb 19 '12 at 6:20
In OSX you have Apple-R at boot and you can reinstall system keeping data on only-default-boot partition intact. – ZaB Feb 19 '12 at 11:18
Ok, cool..I guess I'll not partition it then. Thanks! – abhim12 Feb 19 '12 at 12:10
Actually Apple-R hides in a hidden partition... So i is partitioned alsready. There is practical purpose for enterprise to have boot partition of same size and inaccessible by users so that you can easily distribute patched images (dd is faster than disk utility). – ZaB Feb 19 '12 at 13:20

As pointed out in the thread, if you are not good at estimating how big the content of the partition might get, you would have to resize sooner or later.

On the other hand partitioning reduces fragmentation and of course its a safety issue; You cannot delete stuff on a partition that is not mounted. This only counts if you only automount the data partition and mount the system partition on an as-needed basis.

Edit: I am not sure how mac OS handles fragmentation but for linux its a good idea to put certain folders (those with many writes and deletes) on a partition of their own to reduce fragmentation. eg /home /tmp /var/tmp. just to give you an idea: I have 12 partitions on my linux server (5 of them in RAM).

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So, I guess you are recommending I shouldn't partition? To put it simply, what I am trying to figure out is what should I do with my G: on my Win 7 laptop which was a 200GB separate partition I created to store files, folders etc. I do not have any important data on the C:. Now, having them on a external hard drive and all is good. But if I wanted to put the data on the Mac, will having that data in the same partition as the OS X Lion will pose a threat to it in case the operating system stops working completely?? – abhim12 Feb 19 '12 at 6:18
I am not recommending anything, this decision is up to you, do what you are most comfortable with. But you really should think about doing backups of your data, every harddrive can fail. – Baarn Feb 19 '12 at 9:12
Ok, appreciate your suggestions. Thanks! – abhim12 Feb 19 '12 at 12:10

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