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Measuring Fragmentation in HFS+
keyblob8K writes "Amit Singh takes a look at fragmentation in HFS+. The author provides numbers from his experiments on several HFS+ disks, and more interestingly he also provides the program he developed for this purpose. From his own limited testing, Apple's filesystem seems pretty solid in the fragmentation avoidance department. I gave hfsdebug a whirl on my 8-month-old iMac and the disk seems to be in good shape. I don't have much idea about ext2/3 or reiser, but I know that my NTFS disks are way more fragmented than this after similar amount of use."
but I know that my NTFS disks are way more fragmented than this after similar amount of use
Is this based off of instinct, actual data, or what?
As mentioned in the article, HFS+ does defragging on the fly when files are opened if they are less than 20MB. The source code for this is available here, as is a discussion about it that contains input from some Darwin developers.
what type of file system is there where there is no main allocation table just a header then the file then a header then the file so you could theoretically break a disk and still read the half that was good because all pertinent information relating to a file was in one place?
Ext2/3 and reiserfs both have inbuilt defragmentation capabilities. This can be seen, for instance, when you boot an ext2 system after an unclean shutdown and it checks the integrity of the filesystem. Ext3 and reiserfs are both journaling filesystems, which also helps with this problem. This is often strange for new Linux users, as they're used to worrying about their Windows NTFS/FAT32 filesystems. In Linux, it's just not necessary (nor in any Unix derivative such as AIX or BSD that uses those filesystems).
Goto My Computer. Right click the drive to be analyzed. Select tools/defragment now.../Analyze.
This was my PhD Thesis.
It must be pretty damn good if it can outdo NTFS. I have three computers with WinXP (NTFS 5.1) that I run quite a bit of data through on a daily basis, and neither needs to be defragmented very often at all (two of them have never needed defragmentation in more than a year of use). Mind you, I might fall into some special category of people who don't fall victim to fragmentation for some reason. Anyway, my point is, before you make remarks regarding how well this compares to NTFS, and/or how much "Microsoft sucks", consider how well NTFS still holds up considering its age. Another bonus is, I don't risk losing file system integrity if there's a power failure. ;)
Quality, performance, value; you get only two, and you don't always get to pick.
I've had a continued problem on my iBook for the past year or so.
Under HFS+ in Mac OS X Jaguar or Panther, after about a day of having a clean install, fresh partition and format my hard drive starts making clunking noises and the system locks up (without actually freezing) -- then when reboot attempts are made they take aeons.
Under ReiserFS in Gentoo Linux for PPC: never have the problem. Same hard drive. Months of use, never once hear the hard drive being funky. No lockups.
Do I put the blame on HFS? OS X? I just can't figure out this strange problem.
d. Taylor Singletary,
reality technician techra.el
I've got a G4 with an 80 GB root drive which I use all day, every day. Well, almost. It's never had anything done to it, filesystem-maintenance-wise, since I last did an OS upgrade last fall, about eight months ago.Not too shabby, methinks.
I write in my journal
i believe the topic at hand is fragmentation, not how well it works as a filesystem. in that regard, FAT32 and NTFS do have horrible problems with fragmentation, while HFS+ defragments on the fly.
To be honest, I don't worry too much about NTFS. It seems reliable and for my needs performs satisfactorily. I wonder if fragmentation was an issue overly-promoted by companies like Symantec. What does it mean to have a fragmented disk at logical level when the physical layout is hidden by the drive electronics, which could in fact be translating sectors? Do these defragmentation tools take things like the number of platters in to consideration, and can neighbouring sectors be assumed to be in the same cylinder across platters?
Agreed and the fragmentation on NTFS can have subtle effects (such as fragmenting the MFT) that are NOT easily fixed by simply running a defragmentation tool.
NTFS is a modern journaling filesystem. There is no reason for concern while using it over other journaling file systems.
Gamingmuseum.com: Give your 3D accelerator a rest.
it's not how fragmented your disk is, it's what you can do with your fragmented disk that counts.
CVB
free ipod and free gmail!
I'm sure someone else will point this out as well but its worth noting. In 10.3 there is kernel level defragmentation. When a file is accessed the kernel checks to see if its fragmented, then moves it to a area of the disk where it can exist unfragmented. I think there is a limitation to file size under 20MB but it may be higher. This still gets rid of a great deal of fragmenation. Just food for thought.
But not sure how this are managed in linux filesystems, not just ext2/3 and reiserfs, but also in xfs and jfs.
Seriously, with NTFS and HFS+ I see very little fragmentation on both my Wintel and Apple machines.
Both have 40gig HD's and both have applications installed/uninstalled quite often. My PC feels the worst of this as he gets games installed and uninstalled in addition to the apps.
For example the last time I reinstalled either of these machines was back in january(new year fresh install) and since then my pc has felt the install/uninstal of various games usually ranging from 2-5 gigs each. The Apple has been installed and with the exception of updates, plugins, video codecs and basic small apps that get added/upgraded often has done alright.
Right now Norton System Works on my PC is saying the drive is 4% fragmented. Disk Warrior on my Apple is saying the drive is 2% fragmented.
Conclusion: Fragmentation is no longer an issue for the HOME USER(note how i'm not saying your companies network doesn't need to be concerned), unless there still running a FAT32 partition >. which well they deserve to have there computer explode at that point anyway.
Ave Molech Setting
That's not quite correct. In Panther (Mac OS X 10.3, for the uninitiated), journaling is enabled by default: that is, when you first install Panther, it will add journaling to your existing HFS+ disk, and if you're reformatting, it will default to HFS+ (Journaled). However, prior to Panther, there was no journaling support in HFS+, to my knowledge.
Dan Aris
Fun. Free. Online. RPG. BattleMaster.
The main problem with fragmentation is cache-faults. The disk drives assume that you will be reading the following sector;: when you don't, you'll have to wait for the sector you requested to be brought in from disk. This applies even in the face of the tricks you mention.
Religion is regarded by the common people as true, by the wise as false, and by rulers as useful.
I just put my hard drive in my drier when it is fragmented. Since the group of unfragmented bits weighs more than the fragmented ones, The spinning action causes all of those stray bits to attach to the greater mass.
I've often wondered if defragging and defrag utils are more of a placebo for people concernced with system performance. In my experience I've never noticed any perceivable difference after using a defrag util, on either OS8/9, OSX, 95, 98SE or XP. Then again, I've always made sure to have plenty of free space on my disks [and made sure they were fast enough] whenever I've done anything seriously disk intensive like multitrack audio...
I'll turn into a supernova and burn up everything. Well I'll turn into a black little hole and you'll turn into string.
A lot of people simply equate disk fragmentation with slow application execution and opening of data files. While this is the most visible effect that fragmentation has on a system, it's not the only one. If you are dealing with large files (multi track audio, video, databases) then you will get a different kind of performance hit due to the non-contiguous nature of the free space you are writing to. If you want to capture video with no dropouts, you really want a drive that has all of it's free space basically in one location. This allows you to write those large files with no physical disruption in location. Please do not think that the only benefit to unfragmented space is just "my programs launch faster". If you do any real kind of work on your system with large data files, you should know that a defragmented drive is a godsend.
Who is Twirlip of the Mists?
I have a program from there that at startup will check the MFT, swapfiles and other important files and will make each one contiguous collection of disk blocks. Gotta be done then, as you can't lock them once Windows is completely up.
Blar.
Buzzsaw and Dirms -- I admit, the site looks a little seedy, but I've used both of these programs on several machines for upwards of a year and they've done a superb job of keeping my NTFS disks defragmented.
This is a very arcane procedure in XP. I shall try to explain, but only a professional should attempt this.
1. Right click on drive icon, select properties
2. Select Tools tab and click on "Defragment Now"
3. Click on "Analyze"
4. When analysis finishes, click on "View Report"
This shows two list windows, one containing general properties of the disk such as volume size, free space, total fragmentation, file fragmentation and free space fragmentation. The second list shows all fragmented files and how badly they are fragmented.
Jaguar (10.2) has journaled support as well, but you had to enable it as it was not a default option.
Even in 10.3 it's optional, not required, but it's the new default for new disks. Probably because Apple decided that their code was solid enough to put into production. After testing it on 10.2 I agree with them.
http://docs.info.apple.com/article.html?artnum=256 68
Mac OS X: About Disk Optimization
Do I need to optimize?
You probably won't need to optimize at all if you use Mac OS X. Here's why:
The most significant display I've ever seen for the benefits of defragmentation was on a 386 box that had Win 3.11 in 1992. The boot time was cut from two minutes down to 40 seconds and response was very noticeable. I didn't defrag due to any outside encouragement; I happened to find the utility in some drawer on a job site and gave it a try.
... presuming that Win 9x actually performs.
Fragmentation is a performance killer for Win 9x on older machines
m.mmm..myyy
My new laptop, with a 60GB 7200RPM disk, is under two months old, and I'm defragmenting it now. It's been running for 5 minutes, and is 3% complete, on a disk that is 62% full.
20 minutes later, and it's on 17%. That's pretty damn fragmented, in my opinion.
Not bad. That's 8 months of heavy use since my last format.
I gotta bring this to work today and see what that machine's like. My co-worker has been complaining that he doesn't have a defrag utility since he got OSX. I've been telling him that I don't think it matters. Now I can prove it to him.
I remember back in the days of my Powermac 8100/80av, we would leave the 2 800mb drives defragging over the weekend because they had like 75% fragmentation.
...spike
Ewwwwww, coconut...
What are you talking about?
No, they don't. But since they borrow their design from BSD's FFS they don't need it either.
Erm, that's fsck. fsck doesn't do defragmentation.
It's true, however performance is severely degraded when disk usage reaches around 90% for classic FFS-like filesystems. While the BSDs can mount ext2 partitions none of them uses ext[23] as default. AIX uses a JFS version that's a bit different from the one you see in Linux, which was based on OS/2's code. I think you're mixing up filesystem integrity with fragmentation. In classic BSD UFS/FFS data is stored in datablocks, which are partitioned in fragments, usually 1/4th of the datablock size. A fragmented file is a file that's stored in non-contiguous fragments. Just that. The performance impact of fragmented files vs the time needed to reorganize the data shows that it's not worth running a defrag program on FFS filesystems.
This paper has some more info on the subject.
It's a perfectly valid test -- it measures how much fragmentation can be observed after a certain amount of use. According to your logic we couldn't compare any properties of NTFS/ReiserFS/FAT32/HFS+ because they work differently.
HAND.
Yes and no, it won't have any long time effect on your performance but there is a short time effect that can be usefull when dealing with audio. On a Mac, using a drive with block sizes of 64K to 256K (ideal when dealing with digital audio, as long as you set the buffer per track size of your daw to the same size as the blocks on your drive) you can gain up to 8 tracks by defraging your drive. Sometimes on large projects I have to record a file or playback the entire session in edit mode (no tracks frozen, everything real-time and not bounced), after editing for a while the daw refuses to play the project, lags, stutter or present some serious drop-outs, I defrag and this is where I get this 6-8 tracks headroom, but that will last only for a day of work and even then (Pro-Tools, Nuendo, Cubase, MOTU DP all present this caracteristic, as for the other I haven't tested them enough to provide meaningfull data).
however, defraging is not the same for every defrag utility. For example, I was working with Avid Audiovision about 5-6 years ago on a TV show, it seems that defraging a drive hosting files created or edited with Audiovision with Speed Disk by Symantec would actually corrupt the entire projects contained on the drive (the biggest mistake and the only serious one I had in my career, I didn't loose my job but my boss did loose his temper, live and learn!), audio file were not readable at all after, it was actually a documented bug of Audiovision and I even think it was affecting every OMF files not just the ones used by Audiovision (not sure about this though), thats what happens when your boss won't let you RTFM. Only Disk Express, some Avid defrager or, later, Techtool could defrag those drives.
On a side note, in the Classic mac (7-9.2), defragmenting your drive was also a way to prevent data corruption, actually its the other way around, not defraging would lead to data corruption. I don't know if its also the case with NTFS, EXT2 et al.
Mostly because they end up re-installing the OS every year or so!
Competition Good, Monopoly Bad.
The cache on the disk. And while we do not REALLY know, the described behaviour is a common and proven strategy. Remember that the disk does not have a lot of information to go by; it basically just sees request to read individual sectors. More or less.
Religion is regarded by the common people as true, by the wise as false, and by rulers as useful.
Result: you have a bunch of large files, all very fragmented, and the free space is very fragmented.
Does anyone else think that statement is a bit odd? Maybe it's just me, but I think he's being a little bit presumptuous about the programming skills of the average geek site browser.
Transistors and Beer!!
My reccollection of the OS/2 HPFS file system from IBM was that in many cases it would purposely fragment to take advantage of the disk spin, thus using fragmentation to increase performance.
Defrag utils for OS/2 had options to only defrag if there were more than 3 extents, to avoid nullifying this effect.
funny, years after the death of OS/2, it still kicks ass on much what we use now.
That would be well and good if the problem were otherwise insurmountable. But, it turns out, we've known how to minimize, if not entirely eliminate, filesystem fragmentation for twenty years now - since the introduction of the BSD Fast File System.
It doesn't take expensive (in time, if not in money) tools. All it takes is a moderately clever block allocation algorithm - one that tries to allocate a block close in seek time to the previous one, rather than just picking one at random.
The fundamental insight that the authors of FFS had was that while there may only be one "optimal" block to pick for the next one in a file, there are tens of blocks that are "almost optimal" and hundreds that are "pretty darn good." This is because a filesystem is not a long linear row of storage bins, one after another, as it is treated by many simplistic filesystems. The bins are stacked on top of each other, and beside each other. While the bin right next to you might be "best", the one right next to that, or in another row beside the one you're on, or in another row above or below, is almost as good.
The BSD folk decided to group nearby bins into collections and try to allocate from within collections. This organization is known as "cylinder groups" because of the appearance of the group on the disk as a cylinder. Free blocks are managed within cylinder groups rather than across the whole disk.
It's a trivial concept, but very effective; fragmentation related delays on FFS systems are typically within 10% of optimum.
This kind of effectiveness is, unfortunately, difficult to achieve when the geometry of the disk is unknown -- and with many modern disk systems the actual disk geometry is falsely reported (usually to work around limits or bugs in older controller software). There has been some research into auto-detecting geometry but an acceptable alternative is to simply group some number of adjacent blocks into an allocation cluster. In any case, many modern filesystems do something like this to minimize fragmentation-related latency.
The gist of this is that Microsoft could have dramatically reduced the tendency towards fragmentation of any or all of their filesystems by doing nothing else but dropping in an improved block allocator, and done so with 100% backward compatibility (since there is no change to the on-disk format).
Maybe it was reasonable for them to not bother to so extravagantly waste a few days of their developers' time with MS-DOS and FAT, seeing as they only milked that without significant improvement for eight or nine years, but it's hard to explain the omission when it came to Windows NT. NTFS is a derivative of HPFS which is a derivative of FFS. They had to have known about cylinder group optimizations.
So the fact that, in 2004, we're still seeing problems with filesystem fragmentation absolutely pisses me off. There's no reason for it, and Microsoft in particular ought to be ashamed of themselves. It's ridiculous that I have to go and degragment my WinXP box every few months (which takes like 18 hours) when the FreeBSD box in the basement continues to run like a well-oiled machine despite the fact that it works with small files 24 hours a day, 365 days a year.
Hey Microsoft: You guys have like fifty billion bucks in the bank (well, ok, 46 or 47 billion after all the antitrust suits) and yet you can't even duplicate the efforts of some hippy Berkeleyite some twenty years after the fact? What's up with that?
(I mean "hippy Berkeleyite" in an affectionate way, Kirk. :-)
jim frost
jimf@frostbytes.com
parted? I thought that was only used to fiddle with FAT...
Parted
Fellowship 9/11
A drive is not one dimensional, it is three dimensional: Rotation, platter, track. It is this geometry that BSD FFS takes advantage of to avoid large fragmentation-related delays, since while there may only be one "optimal" sector to use there are quite a few that are "nearby" in terms of rotation, seek, or platter.
jim frost
jimf@frostbytes.com
There are so many comments already posted to this topic that seem to not grasp the following point, that I think the best way to deal with it is to start a completely new thread. I'm sorry if it seems more than a little obvious to some of you:
:-), such as until you would need to perform disk maintenace anyway for lots of other reasons in any 'reasonable' file system. A typical media file is probably Type 1 in 99%+ of cases.
.txt format, while it is stll being edited by its creator. (type 2). (That same document may behave as effectively Type 1 once it is finished, only to revert to type 2 when a second edition is created from it.)
.doc file, that may become longer for obvious reasons like more text, but may also become longer for less obvious reasons (such as the hidden characters created when you make some text italic or underlined). (These are reasons that are not obvious to most end users, and often not predictable in detail even to people who understand them better). The default configuration for a Windows swap file is type 2a. It is likely to be hard for an automated system to predict the final size of Type 2a files, as that would imply a software system of near human level intelligence to detect patterns that are not obvious and invariant to a normal human mind. It may be possible to predict in some cases only because many users are unlikely to make certain mistakes, (i.e. cutting and pasting an entire second copy of a text file into itself is unusual, while duplicating a single sentence or word isn't).
.bmp, which will only get larger or smaller if the user changes the color depth or size of the image, and not if he just draws something else on the existing one.). A good portion of users (not all by any means) will learn
.zip) is hopefully a 3b, but only until it is run, then the contents may be of any type. A typical Microsoft patch is a 3a (it will somehow always end up longer overall, but you never know just what parts will vary or why).
:-).
There are fundamentally only a few types of files when it comes to fragmentation.
1. There are files that simply never change size, and once written don't get overwritten. (Type 1). Most programs are actually type 1, if you use sufficiently small values of never
2. There are files that will often shorten or lengthen in use, for example a word processor document in
Of type 2, there are files of type 2a. Files that may get either longer or shorter with use, on a (relatively) random basis. (as a relatively simple case, a
Then there are files of type 2b. Files that get longer or shorter only for predictable reasons, (such as a Windows
what to expect for these files, which suggests a well-written defragger could theoretically also auto-predict the consequences of the changes a user is making).
3. Then there are type 3 files, which only get longer. These too have predictable and unpredictable subtypes. Most log files for example, are set up to keep getting longer on a predictable basis when their associated program is run (type 3b). Anything that has been compressed (i.e.
4. Type 4 would be files that always get smaller, but there are no known examples of this type
These types are basic in any system, as they are implied by fundamental physical constraints. However, many defrag programs use other types instead of starting from this model, often with poor results.
In analyizing what happens with various defrag methods, such as reserving space for predicted expansion or defragging in the background/on the fly methods, the reader should try these various types (at least 1 through 3), and see what will happen when that method is used on each type. Then consider how many of those type files will be involved in the overall process, and how often.
For example, Some versions of Microsoft Windows (tm) FAT32 defragger move files that have been accessed more than a certain number of times (typically f
Who is John Cabal?
Ideally you wouldn't see your harddrive thrash when booting...
actually, Darwin/OS X has a really nifty feature called BootCache that collects information at boot time and primes the read-ahead on subsequent boots to smooth things out... everyone found out the hard way when it was mildly broken in an update to 10.2 exactly how much difference it makes (it knocks about 2/3 off the boot time of my PowerBook).
see Amit Singh's excellent article for more info, there's a chunk on BootCache at the bottom of this page.
Journalling has existed since 10.2.2 (at least on the Server end; I believe the consumer end too, except you had to enable it via a terminal command), so... ^_^
OK, I was being a bit snobbish in saying it is not a 'real filesystem', it does have its uses - small devices, floppies, etc. BUT, even when it was originally designed it was considered primitive it had many known flaws, among those: it is very easily fragmented (what we are all talking about, no redundancy to help recover from failure and wastes quite a bit of disk space.
My comparison between NTFS and FAT is valid because if you are running Windows, those are the only two filesystems you have to choose between. Comparing NTFS with, for instance, ReiserFS is not really interesting because they're not really alternatives to each other. Unless you choose your operating system based on what filesystems it supports...
The article was comparing HFS+ to NTFS, not windows filesystems. You your self said NTFS deals with fragmentation far better than many other file systems, most notably FAT (emphasis mine) which implies you were not only comparing NTFS to other windows file systems but to many other filesystems. It was the apparent straw man argument that I was pointing out. NTFS is leaps and bounds better than FAT, I 100% agree with you on that. It could be better, and I wish it was open source (last I checked it was not) but is still the best option window users have.
Underloved Movies and Pub Quiz: donotquestionme.org
A word about browsers (and any thing else that requires change):
People, in general (more than 50% of them), prefer to resist change, and for that matter, extra work and/or thinking. It's just the way they are. It's what explains product loyalty. In this case, the product loyalty is browser based.
In my job, as a web server support admin, I find that 95%, or more, of the people I speak with in support situations are not even aware of the alternatives available to them. In fact, just last Sunday, a friend of mine was showing off his new Power Book to me (by the way, even though I am a complete Linux advocate, you have to give credit where credit is due: Mac has a great GUI). I had to laugh during his enthusiastic demo of Mac OS X's features when my friend opens up Safari and goes, "Check this out. It's a feature called 'tabbed browsing.'" He was a kid in a candy store and had just found new, profound flavor of buble-gum or something. But, how could I not laugh at this previously 100% Windows user's intron to me of something that I began using in Opera, back around 5.x-6.x (I really don't remember if 5.x had tabs or not. I really don't care since that browser drives me crazy. But that's just me.) Translation: it's be around for years. In my work day I begin with 12-13 of them opening in FireFOx (NT 2000 doesn't like that, even with 512MB RAM, but it gets by well enough). The number of tabs only increase from there, unless there's an accident of closing a tab. But no big deal there either, I just open another one and then drag it back between where I normally would have it in my list of tabs. You won't find any thing like that in a browser direct from MS.
Another example: my co-workers, particularly the NT techs. Most, certainly not all (thank God), of our NT techs still use IE for their work. I don't really know what they need for their work, but I've seen their desktops and their taskbars; WHAT A MESS! It's beyond me why they would waste their time with a browser (read: IE) that doesn't organize their open web pages into one taskbar entity, because they DO use other programs on the NT 2000 desktop, which we all must use at my job, regardless of the servers we admin for. (If you haven't guessed yet, I don't admin for NT servers, I get the please and ease of admining for Linux boxes. And a big THANK GOD for that!)
Back to my point: most people are not aware of features in other browsers AND if they are aware of new inovations (read: tab browsing, which is one reason I will never go back to IE) they are not in any hurry to change and think and evaluate something that, however troubling it can be at times: pop-ups, vulnerbilities, "________________" [fill in the blank], lack of inovation, etc.
So what if most of /. visitors are Windows based? There are plenty of better choices to MS products, even on their own OS platform. But, people the world over resist change; they get stuck in a rut, good or bad in it's results, and they either don't like to change, don't "need" to change, or cannot change. Thus, the end result is resistance to change; for the better or for the worst.
Tell ya what: FOAD.
Ah, liberal tolerance rears its head again.
Bush lied, Bush continues to lie, and our country is far, FAR more in danger now than when we started this stupid fucking war.
I'd be interested in the metric you use to compute danger, seeing as how there have been exactly zero terrorist attacks on US soil since 9/11. (By the way, were you out protesting the "stupid fucking war" in Serbia, or are Democrats allowed to invade sovereign nations who pose no external threat?)
Bush said he was 100% certain that Saddam had massive stores of WMD and a nuclear program.
Is it just barely possible that maybe he really did believe that, and he was mistaken? Intelligence agencies have been known to make mistakes before. Never mind, I forgot he's from Texas and worked in the oil industry so he's obviously made a pact with Satan.
Oh, but of course, he never ACTUALLY said it. He just IMPLIED it, which makes it all ok, doesn't it? It was a failure of intelligence, which means it ain't his fault! Nothing is his fault! And I mean shit, who needs morals when you're having to deal with them dirty hippie commie faggot libruhls and that libruhl media?
It's amusing watching you guys get progressively more unhinged. Kerry should be leading Bush by a healthy margin given the Iraq situation and that the economic recovery isn't completely visible yet, but when your talking points are all variations on "Bush is a fascist", you can't expect much from the middle. I'm not a huge fan of Bush, but I'll be enjoying his victory on election night just envisioning the enragement of the left.
How to solve most of our problems: 1.Lots of nuclear plants. 2.Cure aging.
If we take the extremely generous assumption that foreign terrorists attack the US every 8 years, for you to make an even remotely reality based assessment of our relative security since 9/11 I'd say you need to wait at least 12 years without any attacks.
Granted, the grandparent would have difficulty proving his assertion that we are in much greater danger now, but I'm sure it could be proven that we have many more enemies. That's not exactly comforting.
We hope your rules and wisdom choke you / Now we are one in everlasting peace
You are forgetting two embassies in Africa and an American Warship. All of those are American soil. So it is not an attack every eight years.
Strange women lying in ponds distributing swords is no basis for a system of government.
One thing people rarely talk about is how fast HFS+ is. Or perhaps how slow UFS on the Mac with OS X is. But the difference is more than dramatic: a clean install of OS X using HFS+ can take less than half an hour - including the developers tools. The same procedure using UFS seems to never end.
It might be the way they've 'frobbed' UFS for use with OS Server, but UFS really gives high priority to disk ops with GUI ops taking the back seat, and yet HFS+ is in comparison blazingly fast.
I believe in a good clean machine like anyone, and I do see the probability DiskWarrior will be needed now and again, but the speed alone is quite a pedigree for HFS+ IMHO.