[TriLUG] Help on disk managment: LVM vs. ZFS

[mr-trilug via TriLUG]

My system:
     Ubuntu 16.04
     LXDE installed

     HD.1    750 GB as LVM with root, home, swap sections, in Samsung 
RV515 laptop

         and for backup and additional storage:
     HD.2    320 GB, 4 partitions
         or    --- one at a time goes in external HD case
     HD.3    120 GB LVM with 2 sections (but not yet recognized or 
mountable.

Q1: Would I benefit from installing ZFS to use instead of LVM?

"ZFS is a combinedfile system 
<https://en.wikipedia.org/wiki/File_system>andlogical volume manager 
<https://en.wikipedia.org/wiki/Logical_volume_management> "Zettabyte 
File System"     ZFS does away with partitioning, EVMS, LVM, MD, etc. 
The available disks (of any size) are used to the best of their ability. 
Compression can be used to increase bandwidth. (q.v. Reiser 4, and cloop?)"
cf.: https://wiki.ubuntu.com/ZFS

Q2: How to progress from status, below, to a mountable status (pv and vg 
exist but lv does not)

fdisk outpu:

Disk /dev/sdb: 110.4 GiB, 118526284800 bytes, 231496650 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0xd389a7da

Device     Boot     Start       End   Sectors  Size Id Type
/dev/sdb1            2048 115000000 114997953 54.9G 8e Linux LVM
/dev/sdb2       115001344 231496649 116495306 55.6G 8e Linux LVM


lvm output

--- Physical volume ---
   PV Name               /dev/sdb1
   VG Name               120g-vg
   PV Size               54.84 GiB / not usable 3.34 MiB
   Allocatable           yes
   PE Size               4.00 MiB
   Total PE              14037
   Free PE               14037
   Allocated PE          0
   PV UUID               1xzJUw-vhbS-kLMc-IjtT-bLtm-WeqM-NFH4Ty

   --- Physical volume ---
   PV Name               /dev/sdb2
   VG Name               120g-vg
   PV Size               55.55 GiB / not usable 2.47 MiB
   Allocatable           yes
   PE Size               4.00 MiB
   Total PE              14220
   Free PE               14220
   Allocated PE          0
   PV UUID               fN0ide-WeXH-uJex-z4nQ-nyUo-ZSeK-VfrIJw


  --- Volume group ---
   VG Name               120g-vg
   System ID
   Format                lvm2
   Metadata Areas        2
   Metadata Sequence No  1
   VG Access             read/write
   VG Status             resizable
   MAX LV                0
   Cur LV                0
   Open LV               0
   Max PV                0
   Cur PV                2
   Act PV                2
   VG Size               110.38 GiB
   PE Size               4.00 MiB
   Total PE              28257
   Alloc PE / Size       0 / 0
   Free  PE / Size       28257 / 110.38 GiB
   VG UUID               7b1yjA-MW9S-zcwX-e8MO-y7BP-YCPs-HGDqlP

===============
Michael Rulison
    919 205 9168 (mobile phone)
    3256 LEWIS FARM RD, RALEIGH  NC 27607-6723