Where does the SL phantom lurk???

[Buzz]

External FW drive getting a little overstuffed, so called up a new, much bigger recruit, to take its place. Cloned the old guy onto the newbie, and magically, about 35GB disappeared... All the folders were identically sized after cloning, except for the System, which shrunk about 60MB. After swapping connections, and finally booting from the spacious newcomer, it immediately plumped up by about half of what I thought had been reclaimed space. Too many gremlins and goblins to wrap the brain around; what gives? The smaller, slower, older drive does have about 20GB surplus stuff that I was contemplating tossing, and with its 35GB of phantom data, I thought cleansing and re-cloning might pare it down to a usable capacity again, as long as nothing more is added to it. It's the gray matter/dark matter[?] that's confusing... I kinda understand drives developing some of it over time, but swapping ports and cables for a simple reboot, actually initial boot, from a drive seems awfully mundane to sprout about 18GB of the stuff. The phantom bloatware exceeds the capacity of the entirety of the capacities of my first fifteen years of Macs. Can this be 'splained?

Thanks.


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[freeradical]

Maybe you now have bigger file allocation blocks that leads to more efficient use of the drive?

[C(-)ris]

Probably temp files, cache files, or other things. CCC excludes some data that is not needed.

[GGD]

Are you checking sizes in a consistent way? I think one change from 10.5 to 10.6 was the way Apple displays disk usage sizes, changing from 1GB = 1024*1024*1024 to 1GB = 1000*1000*1000. So if you looked at the same drive from two different OS versions you would get different results.

And when you booted from the newly cloned drive, it probably re-created a lot of swap/sleep/VM/cache files that don't normally get copied during cloning.

If it were me, I would think a few minutes with Disk Inventory X would find something as large as 35GB faster than it would take to write these posts.

[gabester]

The three preceding posts are on the right track.
You could always make a compressed disk image of the old drive; or of it's folders, if there is static stuff that is not already compressed (i.e. user documents, not images, music, movies)
g=

[Buzz]

Same OS to read info on both drives... it's not the 1000 vs 1024 thingy.
The visible folders add up to much less than what is shown for whole drive(s).
Value after cloning closely approximated visible folders totals, then plumped after use a boot drive w/o copying/adding new data.
No VM's used on either drive.
Size shrinks pretty good when compressed to disk image, so pretty sure it's some sort of cache file(s), but the largest movies I mess with are under 1GB, so still can't figure out 35GB on the oldie, or about half that with the virgin drive.
Will see if Disk Inventory X shows anything interesting over the weekend.
Add'l ideas welcomed.
Thanks.


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