Filesystem for VMWare files

[chuck]

I've am just waiting for everything to back up on my server, than I am going to format it and start over. The only thing is I want to know what filesystem I should use for my .vmdk files.

I've heard xfs and jfs are great for large files, which is basicly all my disk that has my .vmdk files on it is. But I've also heard that I should stick with ext3 cause it is a bit more stable.

Speed is an issue, but the data remaining safe is my biggest concern.

Any suggestions?

[iago]

Well, the only insight I can offer you is into speed. I recently had to downgrade my laptop's harddrive (long story), so currently it isn't big enough for VMWare. So I copied my virtual machines to an ext3 partition on a USB harddrive (which I'm connected to on USB 1.1). I figured I'd give VMWare a shot to see how it would run, and, as far as I can tell, it ran absolutely the same as when I had it on my regular harddrive.

So in terms of speed, VMWare isn't picky.

[chuck]

Its not really what VMWare wants that I'm worried about, its about making VMWare go as fast as it can on this hardware.

I've decided to use XFS as the /srv partition. Currently I'm copying my VM's over, tomorrow I should be able to notice improvements with VMWare. I also am trying ReiserFS for /var and / and have noticed a slight improvement in overall system speed.

And I've also noticed XFS allows more of the drive space when formatted to be used compared to ext3. And, yes, I set the reserved root blocks on ext3 to 0%, and it was still less.

[Chavo]

Probably because XFS doesn't conform to the rigid block sizes norm.  I've never used XFS, but it sounds very interesting.

From wikipedia:

Variable block sizes

The file system block size represents the minimum allocation unit. XFS allows file systems to be created with block sizes ranging between 512 bytes and 64 kibibytes, allowing the file system to be tuned for the expected use. Where a large amount of small files is to be expected, a small block size would typically be used to maximize capacity, but for a system dealing mainly with large files, a larger block size can provide a performance advantage.

That would account for the lack of 'wasted' space with a fixed block size.

[Skywing]

VMware disk files are essentially just going to be big preallocated contiguous chunks so long as your filesystem wasn't badly fragmented or low on space when you moved the files over.  Practically any filesystem should be capable of fielding large sequential files in reasonable fashion.

I would therefore consider things like filesystem integrity in the face of crashes as probably the defining measurement.  Though a VM server would ideally be on stable hardware with backup power.