Use Datasets? Or store everything in my pool?

Moderators: jhartley, MSR734, nola

Use Datasets? Or store everything in my pool?

Post by markpat3rson » Mon Sep 17, 2012 11:34 am

I am running 10.8.1 Server, with 32GB ram.

I plan to build a 3TB x 3TB x 3TB Raid Z (WD Green in Mac Pro), giving me 6TB of usable space.

I'm currently testing with a 500GB USB drive before I purchase the above disks. My test zpool appears on my desktop and is usable as a drive, just like any other. So i'm wondering… are there any cons to using it this way? ie forgo the use of Datasets and just load all my data on to the zpool and create top levels folders for 'Work', 'Photos', 'Movies', etc, rather than datasets for them?

What am I missing here? What are the pros to datasets? i understand you can snapshot and roll them back independently, and I assume send/receive independently, but am I missing anything else?

Am I 'holding it wrong' by not using datasets? :D
markpat3rson Offline


 
Posts: 12
Joined: Sun Sep 16, 2012 8:57 pm

Re: Use Datasets? Or store everything in my pool?

Post by nola » Mon Sep 17, 2012 3:46 pm

The only reason to create datasets under the root pool dataset, is if you want different properties on different datasets. I.e. you want one filesystem with compression on and one with compression off.

-nola
nola Offline


 
Posts: 4
Joined: Wed Sep 12, 2012 9:42 am

Re: Use Datasets? Or store everything in my pool?

Post by pooserville » Mon Sep 17, 2012 11:22 pm

Using multiple datasets means you can do ZFS send/receive options per dataset, so (for instance) I can have Documents and Desktop do a snapshot and 'zfs send' offsite on an hourly basis, while my iTunes gets once a week.
pooserville Offline


 
Posts: 4
Joined: Sat Sep 15, 2012 4:59 pm

Re: Use Datasets? Or store everything in my pool?

Post by jollyjinx » Tue Sep 18, 2012 2:57 am

To have multiple datasets makes sense if you backup differently depending on their location. So in my scenario I do backup my ~/Pictures and ~/Disks ( which contains encrypted sparsebundles ) quite often wereas I never backup ~/Downloads , ~/Library/Application Support/Mail (Downloads|Logs|Caches|Saved Application State)

My home directory is located on puddle in Local/Users/jolly and that are my current filesystems on that pool:

puddle
puddle/Local
puddle/Local/Users
puddle/Local/Users/jolly
puddle/Local/Users/jolly/Disks
puddle/Local/Users/jolly/Downloads
puddle/Local/Users/jolly/Dropbox
puddle/Local/Users/jolly/Library
puddle/Local/Users/jolly/Library/Caches
puddle/Local/Users/jolly/Library/Logs
puddle/Local/Users/jolly/Library/Mail Downloads
puddle/Local/Users/jolly/Library/Saved Application State
puddle/Local/Users/jolly/Pictures


Patrick aka Jolly
jollyjinx Offline


 
Posts: 60
Joined: Sun Sep 16, 2012 12:40 pm
Location: Munich - Germany

Re: Use Datasets? Or store everything in my pool?

Post by roddi » Tue Sep 18, 2012 4:35 am

To add to the above: You can do different snapshots depending on the dataset.

Basically just do it! Use datasets, they are cheap and you are more flexible in what you do.
roddi Offline


 
Posts: 5
Joined: Mon Sep 17, 2012 3:08 am

Re: Use Datasets? Or store everything in my pool?

Post by markpat3rson » Tue Sep 18, 2012 6:21 am

Thanks guys. So helpful! I'm sold.
markpat3rson Offline


 
Posts: 12
Joined: Sun Sep 16, 2012 8:57 pm

child file systems and zfstimemachinebackup.perl

Post by grahamperrin » Sun Sep 23, 2012 12:40 pm

jollyjinx wrote:puddle
puddle/Local
puddle/Local/Users
puddle/Local/Users/jolly
puddle/Local/Users/jolly/Disks
puddle/Local/Users/jolly/Downloads
puddle/Local/Users/jolly/Dropbox
puddle/Local/Users/jolly/Library
puddle/Local/Users/jolly/Library/Caches
puddle/Local/Users/jolly/Library/Logs
puddle/Local/Users/jolly/Library/Mail Downloads
puddle/Local/Users/jolly/Library/Saved Application State
puddle/Local/Users/jolly/Pictures


Thanks, I'm intrigued to see your use of child file systems … only because I can't get recursion to work with your zfstimemachinebackup.perl script – if I'm doing something wrong, sorry.

Side note: after a backup without recursion, on Mountain Lion I can push things easily towards a kernel panic. (This may be a peculiarity of my system, or careless pushing by me – probably no cause for alarm.)
grahamperrin Offline

User avatar
 
Posts: 1596
Joined: Fri Sep 14, 2012 10:21 pm
Location: Brighton and Hove, United Kingdom

Re: Use Datasets? Or store everything in my pool?

Post by jollyjinx » Mon Sep 24, 2012 3:44 am

Well, the script does not support recursion at this level and would be wrong in my case anyways. I'm doing the following in my crontab:


#SHELL=/bin/zsh
1 * * * * cd ~jolly/Binaries/zfs;./autoscrub.perl --scrubinterval=21 >/dev/null 2>&1
1 * * * * cd ~jolly/Binaries/zfs;./autoscrub.perl --scrubinterval=5 --pools=puddle >/dev/null 2>&1
#
# backup to ocean
#
1 * * * * cd ~jolly/Binaries/zfs;for i in "" /Users /Users/jolly{/Pictures,"",/Library,/Dropbox};do ./zfstimemachinebackup.perl --sourcepool="puddle/Local$i" --destinationpool="ocean/puddle/Local$i" --snapshotstokeeponsource=10 --createsnapshotonsource >>/var/log/zfsbackup.log 2>&1;done
*/10 * * * * cd ~jolly/Binaries/zfs;./zfstimemachinebackup.perl --sourcepool=puddle/Local/Users/jolly/Disks --destinationpool=ocean/puddle/Local/Users/jolly/Disks --snapshotstokeeponsource=100 --createsnapshotonsource >>/var/log/zfsbackup.log 2>&1
jollyjinx Offline


 
Posts: 60
Joined: Sun Sep 16, 2012 12:40 pm
Location: Munich - Germany

Re: Use Datasets? Or store everything in my pool?

Post by si-ghan-bi » Mon Sep 24, 2012 4:27 am

Is it possible to add datasets later or is it possible only at the beginning?
How they would appear in the Finder? as drives or as folders in the root?
I'm not used with the concept of datasets.
si-ghan-bi Offline


 
Posts: 145
Joined: Sat Sep 15, 2012 5:55 am

Re: Use Datasets? Or store everything in my pool?

Post by jollyjinx » Mon Sep 24, 2012 8:31 am

you can create and destroy them anytime and you can point them to different mountpoints.
jollyjinx Offline


 
Posts: 60
Joined: Sun Sep 16, 2012 12:40 pm
Location: Munich - Germany

Next

Return to General Discussion

Who is online

Users browsing this forum: ilovezfs and 1 guest

cron