Yeah but that's databases! Whole different game. ;) Jason Sent from my iPhone 5S
> On Mar 16, 2014, at 8:28 PM, roemer <uwe.ro...@gmail.com> wrote: > >> On Monday, 17 March 2014 06:40:02 UTC+11, cap wrote: >> An advantage of snapshots is with active filesystems such as those used by a >> database. For a consist at database backup you of course need to stop the >> program then backup then restart ( or use some database tool if available) . >> The time to create a snapshot is essentially zero so the above start - stop >> is actually practical. Then you use your backup software of choice on the >> snapshot not the active file system. > This is only fine if your database is read-only or you have control on the > update workload. > Most database systems use a combination of no-force+steal buffering and WAL > logging (e.g. MySQL InnoDB or PostgreSQl and basically all commercial RDBMS). > Taking a file-system level snapshot underneath does not guarantee that you > get a consistent snapshot of the database log and data pages. > Together with high update rates, this can be dangerous. Better use the > database system's snapshot facility too before you take the ZFS snapshot. > Granted, open source systems are a bit weak in that regard... > > -- > > --- > You received this message because you are subscribed to the Google Groups > "zfs-macos" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to zfs-macos+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. -- --- You received this message because you are subscribed to the Google Groups "zfs-macos" group. To unsubscribe from this group and stop receiving emails from it, send an email to zfs-macos+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.