Panther Adds "Auto-defragmentation" ability to our Systems??
I just saw a post on Apple's discussion pages about reading other technical posts and articles that can be found here:
http://arstechnica.infopop.net/OpenT...1&m=9900929295
From how I read it, Panther de-fragments files under 20MB on-the-fly. Anyone seen/heard the same information? Are we free (or more free) from the worries of a fragmented system?
http://arstechnica.infopop.net/OpenT...1&m=9900929295
From how I read it, Panther de-fragments files under 20MB on-the-fly. Anyone seen/heard the same information? Are we free (or more free) from the worries of a fragmented system?
Comments
Even if it's a relatively small advantage (I notice that it also moves frequently accessed files to the fastest part of the hard drive) it's just one of those nice little touches that costs almost nothing, functions transparently, and moots that much extra fussing with explicit maintenance utilities.
Slick, even if its effect is subtle enough not to make the list of advertised features.
Originally posted by Amorph
...........Well, defrag utilities certainly aren't needed now........"
Probably the one and only gripe I have ever had with Mac's is around the defrag business.
I could never understand how it was that my PC buddies could defrag without unmounting the harddrive via an external program such as Nortons' etc.
They only had to click a button, and the option was built in...
So could someone please explain this difference to me..as I truly couldn't fathom why Apple neglected this ability in all their older OS systems.
Was it something simply not physically possible or software wise possible ?
Originally posted by Aquafire
So could someone please explain this difference to me..as I truly couldn't fathom why Apple neglected this ability in all their older OS systems.
Defragging was only ever necessary in the days of crappy file systems (eg FAT) and small hard drives. Hence, there were never any really good defrag utilities for the Mac.
Originally posted by Barto
Defragging was only ever necessary in the days of crappy file systems (eg FAT) and small hard drives. Hence, there were never any really good defrag utilities for the Mac.
Hmmm..really ?
"FAT" as far as I recall referred to programs that were designed to work in both 68K & PPC enviroments..
But Mac never had an inbuilt defrag function.
Admitedly my experience with Mac started with OS-7 being run on an B&W SE.
But ...AFAIK nor were any of the earlier mac OS's provided with an inbuilt defrag capacity.
And some of that softare was apparently pretty dirty as well.
So at least for me, the mystery remains...
No-one really wants to search the forums for the pages and pages Kickacha (sp?) wrote about defragging.
Barto
Originally posted by Aquafire
"FAT" as far as I recall referred to programs that were designed to work in both 68K & PPC enviroments..
He's referring to FAT16 and FAT32, Windows 95/98/ME file systems which tend to fragment very easily.
Norton and FWB's HDT had defraggers for HFS back in the 7.x/8.x-days where small HD sizes made the file system much more susceptible to fragmentation (if you only have 10MB free on your disk and you edit and re-save a 20MB file in Photoshop, the likely outcome will be a fragmented file. If you have "only" 1GB free, the file will be stored without fragmentation).
Furthermore, the load/store-algorithms in MacOS X (and Win2K/XP) are much cleverer at avoiding and curing fragmentation to an extend.
Disk defraggers are a thing of the past, they are like RAM doublers (or, on MacOS X, virus scanners) an answer to a problem that does no longer exist, but since they were useful once, a faint collective memory persists about them being necessary.
Originally posted by Smircle
[BDisk defraggers are a thing of the past, they are like RAM doublers (or, on MacOS X, virus scanners) an answer to a problem that does no longer exist, but since they were useful once, a faint collective memory persists about them being necessary. [/B]
And screen savers ! oh wait damnit there back.. damn lcds
http://apple.slashdot.org/apple/03/1...id=185&tid=190
If the file system under Panther does as advertised... then I blew money on Diskwarrrior a month ago.
Screed
Originally posted by Amorph
Well, defrag utilities certainly aren't needed now.
Even if it's a relatively small advantage (I notice that it also moves frequently accessed files to the fastest part of the hard drive) it's just one of those nice little touches that costs almost nothing, functions transparently, and moots that much extra fussing with explicit maintenance utilities.
Slick, even if its effect is subtle enough not to make the list of advertised features.
the one thing i would worry about was if, during all this potential file movement, something like a power outage could kill files that aren't even open, but are int he process of being moved. i assume they could not do this before a journaled file system, right?
But the process of a well thought defragmentation scheme should be:
Read the fragment
Write a copy of the fragment to the new position
Confirm the write
Delete old fragment copy
Repeat
Screed
Originally posted by sCreeD
Correct. From what I've read the defrag functionality and journaling go hand-in-hand.
But the process of a well thought defragmentation scheme should be:
Read the fragment
Write a copy of the fragment to the new position
Confirm the write
Delete old fragment copy
Repeat
Screed
You're definitely right, that's how it should work, in theory. "In theory, communism works, in theory" - H.J.S. But we're talking about Panther here. If it can destroy firewire drives and corrupt one's home with FileVault with impunity, it can do a lot of other strange things as well.
Originally posted by sCreeD
From firsthand experience, NTFS is no better. I check my users' hard drives on occasion and large files like the Outlook mailbox file can sometimes be 7000+ fragments on a relatively vacant hard drive! Sheesh.
If the file system under Panther does as advertised... then I blew money on Diskwarrrior a month ago.
Screed
DiskWarrior defrags the disk directory and optimizes it (thus allowing you to often recover vanished files after a disk crash). It doesn't defrag the actual files. To do that you need something like Drive 10 or the eventually-at-some-point-to-be-released Tech Tools Pro 4
From Ars:
* -----------------
* |///////////////|
* -----------------
* 0 N (file offset)
*
* ----------------- `´`´`´`´`´`´`´`´`
* |///////////////| } whirr... { STEP 1 (aquire new blocks)
* ----------------- `´`´`´`´`´`´`´`´`
* 0 N N+1 2N
*
* ----------------- -----------------
* | ////////| ===}|/////// | STEP 2 (clone data)
* ----------------- -----------------
* 0 N shhhwip! 2N
*
* -----------------
* :>POOF!<: |////*gleam*////| STEP 3 (head truncate blocks)
* -----------------
* 0 N
Originally posted by Aquafire
Probably the one and only gripe I have ever had with Mac's is around the defrag business.
I could never understand how it was that my PC buddies could defrag without unmounting the harddrive via an external program such as Nortons' etc.
They only had to click a button, and the option was built in...
So could someone please explain this difference to me..as I truly couldn't fathom why Apple neglected this ability in all their older OS systems.
Was it something simply not physically possible or software wise possible ?
if you happen to compare the way the mac utils and pc ones defrag, you will notice the pc ones always have a nice chunk of 'unmovable' data, and the macs dont, thats because the macs can defrag everything, whereas the pc cant because its still running the os on the drive.
Apple is really packing in some uber cool features under the radar. I have to say I'm real impressed. This auto defrag is turned along side journaling, and having lost an drive before I am definitely going to activated Journaling.
However what is everyone's thoughts on this:
"Drives are defragged to allow the OS to access the files faster."
Are you so sure?
I have talked with a senior OS designer (one of the non-free ones) and his view is that these days, defragging does more damage than it saves.
Why? Drives generally have large caches on them and multiple platters / read heads.
Noting this, the fastest way to get data off a drive might not be a straight line. Its looks pretty when you run the different utilities and makes the home makers of whom believe everything should be put away neat and tidy, but the engineer had mentioned that being defragged means you loose a lot of advantages of those multiple readheads and cache. He claimed that it was actually better to leave your drive to its own devices, allowing for about 30% free space at all times, and you will see a speedup over a defragged drive.
I didn't believe it at first, but his arguments did make a lot of sense even though it went against everything I had learned before. He actually mentioned if he had his choice, he'd make certain defraggers would NEVER work, but the market believes that these are necessary so its easier to have these things included as well as supporting third parties, so its there.
Would it slow down or speed up a drive, and how about a PowerBook drive that I'm always squeezing down to the last few hundred megs, to the point where OS X sometimes nags me to free up space.
Originally posted by Amorph
Even if it's a relatively small advantage (I notice that it also moves frequently accessed files to the fastest part of the hard drive)..
This is off topic: how does one arrange the OS to be on the fastest part of the hard drive during installation/partitioning? Would it be at the top of the partition box or the bottom part?