Re: [zfs-discuss] Injection of ZFS snapshots into existing data, and replacement of older snapshots with zfs recv without truncating newer ones

2012-01-16 Thread Matthew Ahrens
On Thu, Jan 12, 2012 at 5:00 PM, Jim Klimov jimkli...@cos.ru wrote: While reading about zfs on-disk formats, I wondered once again why is it not possible to create a snapshot on existing data, not of the current TXG but of some older point-in-time? It is not possible because the older data

Re: [zfs-discuss] Injection of ZFS snapshots into existing data, and replacement of older snapshots with zfs recv without truncating newer ones

2012-01-16 Thread Jim Klimov
2012-01-16 23:14, Matthew Ahrens пишет: On Thu, Jan 12, 2012 at 5:00 PM, Jim Klimov jimkli...@cos.ru mailto:jimkli...@cos.ru wrote: While reading about zfs on-disk formats, I wondered once again why is it not possible to create a snapshot on existing data, not of the current TXG but

Re: [zfs-discuss] Injection of ZFS snapshots into existing data, and replacement of older snapshots with zfs recv without truncating newer ones

2012-01-16 Thread Matthew Ahrens
On Mon, Jan 16, 2012 at 11:34 AM, Jim Klimov jimkli...@cos.ru wrote: 2012-01-16 23:14, Matthew Ahrens пишет: On Thu, Jan 12, 2012 at 5:00 PM, Jim Klimov jimkli...@cos.ru mailto:jimkli...@cos.ru wrote: While reading about zfs on-disk formats, I wondered once again why is it not

Re: [zfs-discuss] Injection of ZFS snapshots into existing data, and replacement of older snapshots with zfs recv without truncating newer ones

2012-01-13 Thread Edward Ned Harvey
From: zfs-discuss-boun...@opensolaris.org [mailto:zfs-discuss- boun...@opensolaris.org] On Behalf Of Jim Klimov Perhaps I need to specify some usecases more clearly: Actually, I'm not sure you do need to specify usecases more clearly - Because the idea is obviously awesome. The main

Re: [zfs-discuss] Injection of ZFS snapshots into existing data, and replacement of older snapshots with zfs recv without truncating newer ones

2012-01-12 Thread Jim Klimov
2012-01-13 7:26, Steve Gonczi wrote: JIm, Any modified block (in absence of a snaphot) gets re-written to a new location and the original block is freed. So the earlier state you want to go back and snapshot is no longer there, The essence of taking a snapshot is keeping the original blocks