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does it?
Authored by: poenn on Dec 12, '04 10:15:53AM

"beyond what OS X does automatically?"

does os x really do that, i didn't think so??
as i unterstand, os x does "optimize" the disk after installing software. but i thought this would only do prebinding, not defragmenting?

can anyone explain that to me? :-)

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yes it does.
Authored by: rhowell on Dec 12, '04 11:19:40AM

From the link above:

On-the-fly Defragmentation
When a file is opened on an HFS+ volume, the following conditions are tested:

If the file is less than 20 MB in size
If the file is not already busy
If the file is not read-only
If the file has more than eight extents
If the system has been up for at least three minutes

If all of the above conditions are satisfied, the file is relocated -- it is defragmented on-the-fly.

Hot File Clustering

This optimization is currently available only on boot volumes. Hot File Clustering is a multi-staged clustering scheme that records "hot" files (except journal files, and ideally quota files) on a volume, and moves them to the "hot space" on the volume (0.5% of the total filesystem size located at the end of the default metadat zone, which itself is at the start of the volume). The files are also defragmented.


A defragmenting tool should not move a file into the hot file area, nor should it move a file out of the hot file area. Doing so might degrade performance!

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