[neoben]

I loved the idea of time machine, but it has a fatal flaw that makes it unusable for me, and maybe others too...

Large files that have small changes often will get entirely backed-up every hour.

So, if you have a >1GB Entourage mail database, a 5GB Parallels virtual drive, a large Aperture database, etc.... this files are likely to be backed up every hour, which may mean almost constant disk access!

The fix for this is easy. All TM needs is to have an option to not only backup or not backup a file, but also to backup 'when changed' or backup 'on a schedule'.

That way, most files can be backed-up 'when changed', but files like Entourage DB or a Parallels HD can be backed-up on schedule, such as once per day.

Until that feature makes it in, I'll have to stick with SuperDuper (hoping it's updated soon..!)

Anyone else find this issue to be a deal-breaker for TM?

Best,

Ben
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neo-fight.tv - {The Weekly Technology Podcast}

[Horsepoo!!!]

Yeah, Time Machine is somewhat of a hack...

And because ZFS wasn't ready in time, it's looking less and less likely that Time Machine will use ZFS's capabilities to do this type of thing the right way.

[besson3c]

Originally Posted by Horsepoo!!! 

Yeah, Time Machine is somewhat of a hack...

And because ZFS wasn't ready in time, it's looking less and less likely that Time Machine will use ZFS's capabilities to do this type of thing the right way.

How will ZFS change matters?

[Horsepoo!!!]

Originally Posted by besson3c 

How will ZFS change matters?

It won't back up the entire files if Time Machine doesn't know how to handle incremental backups...just binary changes.

Right now, when Time Machine doesn't know how to do incremental backups, it just copies the entire changed file. And in neoben's situation, this is unacceptable since huge files like Entourage databases will get copied over to the backup drive every X amount of time if a new e-mail was received.

The current solution is to make Time Machine ignore certain folders and back these up manually from time to time.

[besson3c]

Originally Posted by Horsepoo!!! 

It won't back up the entire files if Time Machine doesn't know how to handle incremental backups...just binary changes.

Yeah, I was hoping this would make Leopard. Has it been confirmed that ZFS provides file system level revision tracking?

[Horsepoo!!!]

Originally Posted by besson3c 

Yeah, I was hoping this would make Leopard. Has it been confirmed that ZFS provides file system level revision tracking?

From what I understood of ZFS, yes. I'm hoping I understood correctly. At the file system level, files represented as a bunch of small chunks of data. These chunks can be contiguous on the disk or scattered, it doesn't matter (well it does matter if speed is important which is why defragmenting is important on some systems). But these chunks can be used as a way to track revision.

So if an Entourage database sees some changes (like 5 new e-mails) only a few chunks of data of the entire group of data chunks will have seen some changes...

So if  represents a unchanged chunk of data and  represents changed data, the file system will be able to keep track of revisions:

Before change to file: 
After change to file: 
with  data chunks being backed up. These two red chunks can be reconstructed/swapped with the blue chunks to recreate the original file (before changes happened).

[OreoCookie]

Originally Posted by besson3c 

Yeah, I was hoping this would make Leopard. Has it been confirmed that ZFS provides file system level revision tracking?

To my understanding, ZFS' feature works on the file block level, i. e. only changed blocks are actually copied.

[besson3c]

I think this is revealing Horsepoo:

Versioning file system - Wikipedia, the free encyclopedia

It addresses both ZFS and Time Machine. What the article doesn't explain is whether or not it supports tracking the specific bits of data that are altered in a binary file - sort of like a Unix diff except with binary files.

[besson3c]

Originally Posted by OreoCookie 

To my understanding, ZFS' feature works on the file block level, i. e. only changed blocks are actually copied.

That is my understanding too, since a file system has the luxury of being aware of actual data that is changed at such a low level. As it stands, TM is just an application.

[OliverTwist]

Originally Posted by neoben 

I loved the idea of time machine, but it has a fatal flaw that makes it unusable for me, and maybe others too...

Large files that have small changes often will get entirely backed-up every hour.

So, if you have a >1GB Entourage mail database, a 5GB Parallels virtual drive, a large Aperture database, etc.... this files are likely to be backed up every hour, which may mean almost constant disk access!

Have you tried just turning off automatic backups? I plan to do that myself since I deal with large files sometimes. I only need to back up about once every night, so I don't mind manually telling it to back up.

[philc]

I'm using "iPhoto '08 vesion 7.1 (347)" and noticed /home/xxx/pictures/iPhoto Library seems to be one big file now. I do not recall it being this way in previous versions.

Does this mean TM will backup the entire DB including all pictures every time we add a few pictures or change one?

I'm hoping someone will tell me this is some special 'Bundle' or the file structure is different in the latest version?

Thanks,
Phil

[philc]

Disregard last post. If you look at it in Terminal it is just a regular directory.

[mduell]

The lack of binary diffs is a huge shortcoming of Leopard. Make one tiny change to an iMovie or iDVD project and it needs another 5+ GB. Do that a few times and you've blown away 5 years worth of office documents for recovery.

Are Aperture users going to have the same problem? Does Time Machine treat a Vault as one big binary blob?

[Horsepoo!!!]

Originally Posted by mduell 

The lack of binary diffs is a huge shortcoming of Leopard. Make one tiny change to an iMovie or iDVD project and it needs another 5+ GB. Do that a few times and you've blown away 5 years worth of office documents for recovery.

Are Aperture users going to have the same problem? Does Time Machine treat a Vault as one big binary blob?

Haven't used Time Machine yet but I suspect Aperture vault and iPhoto photo library bundle aren't treated as one large file...bundles are actually folders at the file system level but that are treated as files in the Finder. I'm guessing Time Machine actually goes *into* the bundle/folders and only backs up the actual picture files.

[OreoCookie]

Aperture and Time Machine don't play well together yet either. But since those are just bundles, i. e. special folders with files, Time Machine won't copy them as a whole.

[peeb]

It looks to me as though Apple doesn't really care about this, since all of its apps use regular file systems (mail, iPhoto etc) unlike the MS approach of Entourage or Exchange that uses huge database files.

[zerostar]

This is another reason I am dumping Entourage right now, I would however like a better solution, I have been using Synk (and will continue to at work) but TM will be just fine for home use with a bit of tweaking... Right now it is just backing up my home folder. All my bookmarks & web settings are backed up to my iDisk twice a week and I will rotate a full home folder backup to DVD once every 3 months now.

I wish there were a few settings to "tweak" on TM though, it would be nice to have SOME options, or an advanced tab. Get on the ball Apple!

[AppleOptionFour]

I am ONLY backing up user folders.

I know how to replace the apps.

[krove]

Not being able to use Time Machine with Aperture is a real let-down! Also, Aperture not working with Front Row sucks. What has the Aperture team been up to while Leopard was under development?

[gradient]

Overall, Time Machine seems like a waste of time for my needs. Under Tiger, I had Deja Vu set to back up every night to my external, meaning that I always had a bootable current-to-the-day backup of my system. If my primary disk every failed, it was a snap to just reboot to the backup volume and be back exactly where I wanted in no time flat. With Time Machine, though, it means having to do a full system restore from the backup volume which is going to take a chunk of time that seems unnecessary.

Not to mention that I don't even see a way to turn off the hourly backups, schedule specific backup times or backup to multiple disks.

Time Machine certainly doesn't work for me in its current state.

[irfoton]

I've read that Entourage 2008 will not be one large database. I've also read that TM works with File Vault just fine.

[CollinG3G4]

How important is your data that it needs to be backed up every single hour? Once a day seems sufficient unless you're like a hardcore professional or super nerd.

[OliverTwist]

Originally Posted by gradient 

Not to mention that I don't even see a way to turn off the hourly backups, schedule specific backup times or backup to multiple disks.

Do you mean manual backups? I'd imagine that's just a matter of keeping it turned off in the preference pane, and control-clicking the dock icon when you'd like to back up.

[gradient]

Originally Posted by OliverTwist 

Do you mean manual backups? I'd imagine that's just a matter of keeping it turned off in the preference pane, and control-clicking the dock icon when you'd like to back up.

By specific backup times, I mean letting me pick when I want it to backup. Normally that would be 4am, but if I'm on night shifts for a week it would be 4pm.

[peeb]

Originally Posted by CollinG3G4 

How important is your data that it needs to be backed up every single hour? Once a day seems sufficient unless you're like a hardcore professional or super nerd.

I think TM is not for the hard-core who already have other options. It's for ordinary folks who never back up. An easy way to automate it.