ways to defragment HFS?

[Bruce Duff]

Hi there

I was wondering if there are any suitbale methods of defragementing a HFS 10.20 server? I susupect there isnt but what do people out there do? I'm ok with vxfs but need to know about this.

Thanks
Bruce

[harry d brown jr]

Bruce,

Back it up and restore it is an option.

live free or die
harry

[Bill Hassell · Accepted solution]

The HFS filesystem doesn't need defragging, or more accurately, it is designed to be fragmented ina very efficient manner. Unlike VxFS (and most other filesystems), HFS creates clusters for files around cylinder groups across the disk and once a file is created, additional space will be allocated within that cylinder group.

Only when the filesystem approaches 80-90% full will this allocation method show any signs of a slowdonw, but *only* when adding new space. If the filesystem is used for a typical database, you can preallocate the space at 100% full with no degradation in performance as the data files are static in size.