Code review comment for lp:~a.skwar/mylvmbackup/zfs

Just some personal comments on Skwar's rev86 branch proposal:

* The idea here, as I understand it, is to be able to create a snapshot of all relevant data necessary to facilitate a "full backup". If you only backup the "DataDir", then you miss out on binlogs, error logs, relaylogs, innodb logs, etc. For us, its simply best to backup the entire "root" mysql dir, /var/lib/mysql/ Inside that we have better organized directories for each aspect of mysql.

* Changing the snapshot size to a percentage won't work for us. Our customers (over 200) all have varying sizes of HD partitions. Some are 2TB, some are 100GB. In all cases, we only allocate 10GB for snapshot space; there isn't any need for more space. Changing to a percentage would, on most servers, cause the script to fail as being unable to allocate space for the snapshot. Perhaps this setting could be changed so that if the last character in the string is '%' it does a percentage or 'G' and it does a fixed size?

* lines 848-859 of r86 confuse me. I've never used ZFS before so cannot speak on its behalf. But I have and do use LVM. You cannot create a snapshot of a specific directory under LVM. You can only snapshot entire logical volumes.The lines mentioned seem to attempt to create multiple snaps of individual directories which is not possible with LVM.

* same goes for lines 981-993. With LVM, there would only be 1 snapshot volume.