Jump to content
hmurchison

Sun confirms ZFS is default Leopard filesystem

27 posts in this topic

Recommended Posts

Advertisement

I think they are going better than well they are done if they plan on releasing it in 5 days to developers. It is pretty amazing that apple was able to get ZFS to boot before Sun was. Although I am sure there was a joint effort there.

Share this post


Link to post
Share on other sites

Does anyone foresee any problems for Hackintosh users with the switch to ZFS? I know the work that has been done on the early betas has been hush hush to keep from getting in an arms race with Apple; So, without getting into too much detail I would appreciate it if the guru's could weigh in on whether or not they think this might be an issue.

Share this post


Link to post
Share on other sites

http://en.wikipedia.org/wiki/File_system_fragmentation

 

Techniques for mitigating fragmentation Several techniques have been developed to fight fragmentation. They can usually be classified into two categories: proactive and retroactive. Due to the hard predictability of access patterns, these techniques are most often heuristic in nature, and may degrade performance under unexpected workloads.

 

 

 

[edit] Proactive techniques

Proactive techniques attempt to keep fragmentation at a minimum at the time data is being written on the disk. The simplest of such is, perhaps, appending data to an existing fragment in place where possible, instead of allocating new blocks to a new fragment.

 

Many of today's file systems attempt to preallocate longer chunks, or chunks from different free space fragments, called extents to files that are actively appended to. This mainly avoids file fragmentation when several files are concurrently being appended to, thus avoiding them from becoming excessively intertwined.[4]

 

A relatively recent technique is delayed allocation in XFS and ZFS; the same technique is also called allocate-on-flush in reiser4 and ext4. This means that when the file system is being written to, file system blocks are reserved, but the locations of specific files are not laid down yet. Later, when the file system is forced to flush changes as a result of memory pressure or a transaction commit, the allocator will have much better knowledge of the files' characteristics. Most file systems with this approach try to flush files in a single directory contiguously. Assuming that multiple reads from a single directory are common, locality of reference is improved.[7] Reiser4 also orders the layout of files according to the directory hash table, so that when files are being accessed in the natural file system order (as dictated by readdir), they are always read sequentially.[8]

 

Bittorrent and other peer-to-peer filesharing clients have an "Antifragmentation" feature that allocates the full space needed for a file when initiating downloads.

 

 

 

[edit] Retroactive techniques

Retroactive techniques attempt to reduce fragmentation, or the negative effects of fragmentation, after it has occurred. Many file systems provide defragmentation tools, which attempt to reorder fragments of files, and often also increase locality of reference by keeping smaller files in directories, or directory trees, close to each other on the disk.

 

The HFS Plus file system transparently defragments files that are less than 20 MiB in size and are broken into 8 or more fragments, when the file is being opened.[9]

 

Share this post


Link to post
Share on other sites

Hi,

 

I do have the same concerns about hackintoshes. People from Sun were only able to boot from ZFS in November 2006. But was it done using a BIOS or EFI based computer? As Apple's computers are using EFI they were able to boot it from EFI. But will Apple make it boot directly to ZFS or will put another boot manger on a tiny partition (formatted in HFS+) instead of writing a driver to EFI? This is for Intel computers but what about PowerPCs. Apple will have to develop new OpenFirmware for PowerPC computers to boot to ZFS. After some a little research on OpenSolaris I was able to find that the next version of GRUB will be able to boot from ZFS. But that depends how Apple's bootloader will load the OS. Will we be able to remove Apple's bootloader to make the computer boot to GRUB and then make GRUB load 10.5 Leopard. I don't think so. Another think that is very important is the development of Darwin. We currently use the Darwin bootloader to boot our computers to Tiger but will Darwin support ZFS or will remain HFS+ only.

 

This will all depends how Apple sees this. For them, this may be a great way to stop people from using hackintoshes because I don't think any computer BIOS manufacturer will develop an ZFS capable BIOS. They just wait Windows to be able to boot on EFI computers.

 

I think will be more informed on all of this on Monday after the WWDC keynote!

Share this post


Link to post
Share on other sites

Do you want to know something unbelievably amazing that Apple could do?

 

Remember how the GUID Partitioning Scheme on the Intel Macs use a 200 MB FAT32 partition?

Do you know how to boot experimental file systems under Linux?

 

You use a /boot partition that IS readable, that houses your kernel and everything needed to start the OS.

 

Some foresight? maybe...

Share this post


Link to post
Share on other sites

Thatd be great for Intel Macs, but it would require a likely reinstall for PPC macs to create a boot partition non destructively.

Share this post


Link to post
Share on other sites
Um...

 

How would one non-destructively replace their filesystem?

 

It can be done on the XP and 2000 installers - changing FAT32 to NTFS.

I don't know how they do it, but it shows that such a conversion is possible

Share this post


Link to post
Share on other sites

Only if it has considerable space left over on the file system to move all data to the beginning of the disk, shrink the partition, create an all new one at the end, copy over the data, delete data, shrink + enlarge, copy, delete, shrink + enlarge... Seriously risking irrepairably loosing your data forever.

 

It literally isn't just as simple as swapping over your File location identifiers and creating a new partition map.

Well, I guess it "could" be that simple IF there were ZERO fragmentation on the disk and if you made sure that the cluster sizes were identical.

 

But then again, that throws away one of the MAJOR advantages of ZFS... variable cluster sizes. The whole idea of only using as much space as you need and no more... leaving the excess for your meta-files.

 

The most likely solution is that Apple would just implement the Resizing of HFS+ partitions and creating the all new file system afterwards...

That is if they don't just say "plug in your iPod or other External Storage Drive to complete the conversion."

Share this post


Link to post
Share on other sites
I think they are going better than well they are done if they plan on releasing it in 5 days to developers. It is pretty amazing that apple was able to get ZFS to boot before Sun was. Although I am sure there was a joint effort there.
Why is it that everyone gives credits to Apple and not Sun? What says Apple have done anything at all? Why do people seem to belive Sun can't do this stuff alone? It's not like Sun NEEDS Apple, it's just that the filesystem is open source so Apple can use it if they want to.

 

Probably major {censored} that Apple can boot it before Sun to, you have been able to sort of boot it for a while and eventually boot it aswell in the community release, I haven't followed the last builds so I don't know. But it's safe to say that Sun have done work on it.

 

According to this they first booted it August the 1st 2005: http://blogs.sun.com/tabriz/entry/zfs_boot

 

I can't say for sure that Sun helps Apple porting it, or that Apple might pay Sun and eventually submit patches back to Sun either, but what I'm 100% sure in is that Apple doesn't deserv the credit.

 

Call me stupid.. but what is ZFS.. what makes it better?
Ask google.

 

http://www.sun.com/software/solaris/faq.jsp#q_3

http://www.sun.com/2004-0914/feature/

http://www.opensolaris.org/os/community/zfs/

 

Does anyone foresee any problems for Hackintosh users with the switch to ZFS? I know the work that has been done on the early betas has been hush hush to keep from getting in an arms race with Apple; So, without getting into too much detail I would appreciate it if the guru's could weigh in on whether or not they think this might be an issue.
Only issues I see are with the {censored} apps which does use filenames in other "cases" than the names they have in their code, Warcraft III and Photoshop comes to my mind, I already have issues with those in HFSX+ and those will be the same in ZFS, but it's easily solved, but I would prefer if Blizzard and Adobe fixed it instead.

Share this post


Link to post
Share on other sites

Today's Macsurfer site says ZFS as the default on the Mac is BS as it can't be booted. We will soon know Tomorow !

Share this post


Link to post
Share on other sites

Why on earth cant a FS be bootable? Only one thing is required and that is support on the rom/fw and a small update of that is all that is needed...

Share this post


Link to post
Share on other sites

Um... a top secret feature?

 

Remember, there are still 8 top secret features, that we haven't heard about from WWDC06.

 

Desktop

Finder

 

Sure, you could call Stacks one, so make that 7 secret features left.

Share this post


Link to post
Share on other sites

So when will we hear about them if this was a 'feature-complete' release?

 

~Matt

 

 

Um... a top secret feature?

 

Remember, there are still 8 top secret features, that we haven't heard about from WWDC06.

 

Desktop

Finder

 

Sure, you could call Stacks one, so make that 7 secret features left.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Recently Browsing   0 members

    No registered users viewing this page.

×