Re: [zfs-discuss] What's eating my disk space? Missing snapshots?
Thank you very much, this explains it perfectly. I had been coming to the conclusion that the shared data must be what accounts for the "missing" space, but previously my thinking/expectation was that it would be "charged" against the snapshot in which the shared data first appeared. Doing that would probably bring its own complications too though I suppose, so I can see why the decision was made to lump it all together in the "usedbysnapshots" figure rather than complicate the zfs command output further. It does lead to another question though: is there a way to see how much data is shared between any two given snapshots? Thanks again, Matt -- This message posted from opensolaris.org ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] What's eating my disk space? Missing snapshots?
Ha ha, I know! Like I say, I do get COW principles! I guess what I'm after is for someone to look at my specific example (in txt file attached to first post) and tell me specifically how to find out where the 13.8GB number is coming from. I feel like a total numpty for going on about this, I really do, but despite all the input I still don't see an answer to this basic question. I promise this will be my last post querying the subject! Thanks Matt -- This message posted from opensolaris.org ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] What's eating my disk space? Missing snapshots?
I do understand these concepts, but to me that still doesn't explain why adding the size of each snapshot together doesn't equal the size reported by zfs list in USEDSNAP. I'm clearly missing something. Hmmm... -- This message posted from opensolaris.org ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] What's eating my disk space? Missing snapshots?
> Well, I see USEDSNAP 13.8 GB for the dataset, so if you delete ALL > snapshots you'd probably be able to get that much. I agree, it's just hard to see how... > As for "which snapshot to delete to get most space", > that's a liitle > bit tricky. See > rpool/export/home/m...@zfs-auto-snap:monthly-2009-06-2 > 8-20:59, which > has USED 2.45G? If I understand correctly, it roughly > means > rpool/export/home/m...@zfs-auto-snap:monthly-2009-06-2 > 8-20:59 and > rpool/export/home/m...@zfs-auto-snap:monthly-2009-07-0 > 5-13:43 has > about 2.45G of difference. That's what I thought too, but by that logic I'd have thought that if you add up all the "differences", you'd get the total USEDSNAP figure of 13.8GB, but you don't - it only adds up to around 5GB. > > This means: > - Deleting > rpool/export/home/m...@zfs-auto-snap:monthly-2009-06-2 > 8-20:59 > only probably won't save you lots of space, as the > used space would > probably be moved to > rpool/export/home/m...@zfs-auto-snap:monthly-2009-05-2 > 8-08:03 > - Deleting all snapshot on and prior to > rpool/export/home/m...@zfs-auto-snap:monthly-2009-06-2 > 8-20:59 could > give you at least 2.45G space. Yes, that's exactly what happened - the used data all moved to another snapshot, and deleting that snapshot freed it all up (I guess that must have been the point at which I first wrote the large files, or whatever). It seems that the more you start to delete things, the easier it is to see where the total USEDSNAP figure is coming from. It's almost like it can't tell you where the figure is coming from ahead of time - it requires you to take more actions before it can give you a more accurate figure. I'm sure there must be a way to find out though... Thanks, Matt -- This message posted from opensolaris.org ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] What's eating my disk space? Missing snapshots?
Hi, thanks for the info. Can you have a look at the attachment on the original post for me? Everything you said is what I expected to see in the output there, but a lot of the values are blank where I hoped they would at least be able to tell me a breakdown of the USEDSNAP figure As far as I know I'm using zpool version 13 (it might be higher - I didn't upgrade it manually, but I don't know if the updates from /dev repository would have triggered an upgrade at any point) Thanks, Matt -- This message posted from opensolaris.org ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] What's eating my disk space? Missing snapshots?
The guide is good, but didn't tell me anything I didn't already know about this area unfortunately. Anyway, I freed up a big chunk of space by first deleting the snapshot which was reported by zfs list as being the largest (2GB). Doing zfs list after this deletion revealed that several of the numbers had changed - all of a sudden a snapshot that was a couple of hundred MB turned into 5GB, so I deleted that as well. So there must be basically lots of references to data that hide themselves from the surface and can't really be found using zfs list. Is there another tool that helps to visualize disk space usage and references to data, or could one potentially be made? E.g. I regained my disk space by trial and error, but if there had been some kind of visual tool that made it easy to see that "if I delete that snapshot, then that one, I will get 7GB back", that would have been really handy. Thanks, Matt -- This message posted from opensolaris.org ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
[zfs-discuss] What's eating my disk space? Missing snapshots?
Please can someone take a look at the attached file which shows the output on my machine of zfs list -r -t filesystem,snapshot -o space rpool/export/home/matt The USEDDS figure of ~2GB is what I would expect, and is the same figure reported by the Disk Usage Analyzer. Where is the remaining 13.8GB USEDSNAP figure coming from? If I total up the list of zfs-auto snapshots it adds up to about 4.8GB, which leaves about 11GB unaccounted for. Please can someone tell me where I'm going wrong and how I can find out what is using all that extra space? Thanks, Matt -- This message posted from opensolaris.orgm...@opensolaris:~$ zfs list -r -t filesystem,snapshot -o space rpool/export/home/matt NAMEAVAIL USED USEDSNAP USEDDS USEDREFRESERV USEDCHILD rpool/export/home/matt 5.73G 16.0G 13.8G 2.15G 0 0 rpool/export/home/m...@zfs-auto-snap:monthly-2009-04-27-17:53 - 155M - - - - rpool/export/home/m...@zfs-auto-snap:monthly-2009-05-28-08:03 - 90.6M - - - - rpool/export/home/m...@zfs-auto-snap:monthly-2009-06-28-20:59 - 2.45G - - - - rpool/export/home/m...@zfs-auto-snap:monthly-2009-07-05-13:43 - 544M - - - - rpool/export/home/m...@zfs-auto-snap:weekly-2009-07-20-18:23- 1.03G - - - - rpool/export/home/m...@zfs-auto-snap:weekly-2009-07-28-08:01- 191M - - - - rpool/export/home/m...@zfs-auto-snap:hourly-2009-08-02-22:00- 7.18M - - - - rpool/export/home/m...@zfs-auto-snap:monthly-2009-08-04-20:49 - 386K - - - - rpool/export/home/m...@zfs-auto-snap:hourly-2009-08-04-21:00- 251K - - - - rpool/export/home/m...@zfs-auto-snap:hourly-2009-08-04-22:00- 49.9M - - - - rpool/export/home/m...@zfs-auto-snap:hourly-2009-08-07-08:00- 42.6M - - - - rpool/export/home/m...@zfs-auto-snap:hourly-2009-08-08-13:16- 39.5M - - - - rpool/export/home/m...@zfs-auto-snap:hourly-2009-08-08-14:00- 28.6M - - - - rpool/export/home/m...@zfs-auto-snap:hourly-2009-08-08-15:00- 26.7M - - - - rpool/export/home/m...@zfs-auto-snap:hourly-2009-08-08-16:00- 50.6M - - - - rpool/export/home/m...@zfs-auto-snap:hourly-2009-08-08-17:00- 2.72M - - - - rpool/export/home/m...@zfs-auto-snap:hourly-2009-08-10-20:00- 3.48M - - - - rpool/export/home/m...@zfs-auto-snap:hourly-2009-08-10-21:00- 48.6M - - - - rpool/export/home/m...@zfs-auto-snap:hourly-2009-08-10-22:00- 8.83M - - - - rpool/export/home/m...@zfs-auto-snap:hourly-2009-08-11-17:52- 243K - - - - rpool/export/home/m...@zfs-auto-snap:hourly-2009-08-11-18:00- 165K - - - - rpool/export/home/m...@zfs-auto-snap:hourly-2009-08-11-19:00- 45.4M - - - - rpool/export/home/m...@zfs-auto-snap:hourly-2009-08-11-20:00- 38.5M - - - - rpool/export/home/m...@zfs-auto-snap:hourly-2009-08-11-21:00- 38.7M - - - - rpool/export/home/m...@zfs-auto-snap:frequent-2009-08-11-21:45 - 6.00M - - - - rpool/export/home/m...@zfs-auto-snap:hourly-2009-08-11-22:00- 6.91M - - - - rpool/export/home/m...@zfs-auto-snap:frequent-2009-08-11-22:15 - 8.27M - - - - rpool/export/home/m...@zfs-auto-snap:frequent-2009-08-11-22:30 - 7.69M - - - - rpool/export/home/m...@zfs-auto-snap:daily-2009-08-12-07:32 - 0 - - - - rpool/export/home/m...@zfs-auto-snap:hourly-2009-08-12-07:32- 0 - - - - rpool/export/home/m...@zfs-auto-snap:weekly-2009-08-12-07:32- 0 - - - - rpool/export/home/m...@zfs-auto-snap:frequent-2009-08-12-07:45 - 3.87M - - - - ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/z
