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I am currently running Ubuntu 10.04 and my hard disk's Partitioning is set to Master Boot Record with Filesystem type Ext4 (version 1.0).

I have purchased several new Western Digital portable external hard drives (500 GB). When I checked them, they were set to MBR and NTFS.

I have read that GUID is superior to MBR. Is that true? In any case, I have set these portable hard drives to that system instead of MBR. (I can, of course, change them back.) I see no difference in anything, operation-wise or performance-wise. What would be the pros and/or cons of this?

When I formatted these drives as Ext4, however, I see, with no data on the drives, that about 23 GB was being used (for something), reducing the amount of available space by that much.

When I reformatted them as NTFS, I see only 73.5 MB being used, a considerable difference.

Can anyone here comment on the pros and/or cons of these various file systems and how they will benefit (or detract) from my overall usage of these drives?

Or doesn't it make any difference at all? I'm using these drives strictly as storage media.

I thank you for your consideration.

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The 23 GB is not being used for anything, it is just the ordinary 5 % of diskspace marked for being available to superuser only:… – Antti Haapala Dec 29 '12 at 4:50

GPT partitioning (what you call GUID) is newer and has some features that make it better than MS-DOS partitioning (what you call MBR). For example you will need it for disks that are larger than 2 TiB. But not all operating systems recognize it (especially older OS, like Windows XP, but linux distros from a couple of years ago too), and teh same is true for soem utilities, so using MS-DOS partitioning is better if you don't know beforehand what computers you need to connect to, or what applications you are going to use.

Similarly, when you need to exchange data with Windows or Mac OS X users sometimes, it's probably best to use NTFS or even FAT32. Personally I solve this by having multiple partitions on my portable disk. That way I can use the FAT32 partition for when I need to exchange files, and the ext3/4 partition for "personal usage". If you only use them as storage for Ubuntu systems, I'd suggest you use a linux filesystem (e.g. ext3/4) because it will be faster & more stable.

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Thank you for your comment and suggestions. My problem with using ext4 is that it uses a far larger amount of space on my external drive than does NTFS, as I described in my posting. I do not know why this should be. Can you explain? – lhb1142 Oct 25 '10 at 13:45
what do you mean by "used"? how did you check that? – JanC Oct 25 '10 at 17:35
I did a check with an empty ext3 & ext4 filesystem on a 750GB disk, and only had about 200 MB "in use". – JanC Oct 25 '10 at 18:03

there are 2 good page where you can obtain more information :

PERFORMANCE OF FILESYSTEMS COMPARED and Comparison of file systems

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Thank you for your comment. However I had seen and read both of these pages prior to writing my query and they did not answer my questions in a manner understandable by me. – lhb1142 Oct 25 '10 at 13:46

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