Mac OS X - The state of the file system (2011)(arstechnica.com)
arstechnica.com
Mac OS X - The state of the file system (2011)
http://arstechnica.com/apple/2011/07/mac-os-x-10-7/12/#file-system
6 comments
> Corruption in file data is arguably worse because it's much more likely to go undetected. Over time, it can propagate into all your backups. When it's finally discovered, perhaps years later when looking at old baby pictures, it's too late to do anything about it
This applies to every OS I guess (except with ZFS or BTRFS)? This is my biggest concern currently. I'm mostly using one drive with ext4 that I back up from time to time, what if the files silently corrupt and it propagates to my backups, I wouldn't notice until it's too late probably. I guess rsync wouldn't sync the wrong data unless the files have changed since it syncs based on modification stamps. Investing into a proper RAID or ZFS is "expensive". I'm so paranoid about this I'm probably going to do it at some point.
This applies to every OS I guess (except with ZFS or BTRFS)? This is my biggest concern currently. I'm mostly using one drive with ext4 that I back up from time to time, what if the files silently corrupt and it propagates to my backups, I wouldn't notice until it's too late probably. I guess rsync wouldn't sync the wrong data unless the files have changed since it syncs based on modification stamps. Investing into a proper RAID or ZFS is "expensive". I'm so paranoid about this I'm probably going to do it at some point.
So sad. We've been waiting for ZFS (or similar) for years now to no avail. It's one of those things that you know Apple engineers are hitting their head about but there's so much legacy code keeping them on HFS+ that they need some real institutional push to get things ported.
For the adventurous, there's Zevo [1] which is a port of ZFS to Mac OS X that supports all the fine grained details of the operating system:
"ZEVO’s file system is fully integrated into the Mac’s unique OS environment and implements quotas, ACLs, and the HFS+ programming interfaces like search-fs, id lookups, bulk access calls and resource fork stream access."
If I remember it correctly, the company is run by the guy that was responsible for the ZFS-Mac OS X integration at Apple that was canned shortly before 10.6 was released.
[1] http://getgreenbytes.com/solutions/zevo/
"ZEVO’s file system is fully integrated into the Mac’s unique OS environment and implements quotas, ACLs, and the HFS+ programming interfaces like search-fs, id lookups, bulk access calls and resource fork stream access."
If I remember it correctly, the company is run by the guy that was responsible for the ZFS-Mac OS X integration at Apple that was canned shortly before 10.6 was released.
[1] http://getgreenbytes.com/solutions/zevo/
Sadly ZEVO looks to be in trouble, if not dead [1]. Even Don Brady (the lead engineer behind ZEVO) has reluctantly returned to HFS+ on 10.9 [2].
[1] http://jollyjinx.tumblr.com/post/64863395820/time-to-say-goo...
[2] https://twitter.com/DonJBrady/status/393028766554812416
[1] http://jollyjinx.tumblr.com/post/64863395820/time-to-say-goo...
[2] https://twitter.com/DonJBrady/status/393028766554812416
Anyone know why this is being upvoted? Anything new (in 2013) that is suddenly makes this relevant again? (ZFS changed their license? WinFS back as a zombie?)
It's not breaking news or anything, but by definition, "Mac OS filesystem still a piece of crap" won't be.
I assume it's being upvoted because it's interesting and (apparently) timeless.
I assume it's being upvoted because it's interesting and (apparently) timeless.
I'm thinking that the release of Mavericks is probably the impetus. Someone was likely digging around to see if/why an updated file system was/wasn't included in Mavericks.
The paragraph about the hard link errors propagating from one backup to another in Time Machine is pretty scary.
Is there any known solution to this problem? Would running something like Disk Util from time to time detects the errors and fix the filesystem?
Is there any known solution to this problem? Would running something like Disk Util from time to time detects the errors and fix the filesystem?
Depends on the cause of the corruption. If the physical drive is going bad, then diskutil should at least report some errors. But HFS+ doesn't checksum anything. If you have a flaky controller or just an errant solar ray flipping a bit, there's nothing diskutil can do about it. A 0 is as valid a bit as 1, so as far as diskutil can tell, all you did was save a change to a file somewhere.
You can verify your time machine backups periodically though.
You can verify your time machine backups periodically though.
Please Apple give us ZFS so we can all sleep at night.