FORUMS: list search recent posts

LTO Tape Technologies update

COW Forums : Archiving and Back-Up

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
Tim Jones
LTO Tape Technologies update
on May 7, 2018 at 10:42:40 pm

Hi Folks,

It's been a while and with LTO-8 finally shipping in quantity, I thought I'd take a moment and refresh the LTO technologies information as to capacities, speeds, and compatibilities.

Device Interface Native Performance Native Capacity
LTO-1 SCSI, FC 15MB/Sec, 4GB/Hr 100GB
LTO-2 SCSI, FC 30MB/Sec, 108GB/Hr 200GB
LTO-3 SCSI, SAS, FC 40-80MB/Sec, 144-288GB/Hr 400GB
LTO-4 SCSI, SAS, FC 40-110MB/Sec, 144-396GB/Hr 800GB
LTO-5 SAS, F-C 40-140MB/Sec, 144-504GB/Hr 1.5TB
LTO-6 SAS, F-C 40-160MB/Sec, 144-576GB/Hr 2.5TB
LTO-7 SAS, F-C 40-300MB/sec, 144-1,080GB/Hr 6TB
LTO-8 (M8) SAS, F-C 40-300MB/sec, 144-1,080GB/Hr 9TB
LTO-8 SAS, F-C 40-300MB/sec, 144-1,080GB/Hr 12TB

(be sure to scroll horizontally to see the entire table)

While there are "Thunderbolt" and "USB-3" drives being advertised, internally these are simply SAS devices with an adapter to provide the interconnect between the TB or USB interface and the SAS tape drive.

As for compatibility between drives and media types, up through LTO-7, all drivers are capable of writing 1 generation back, and reading 2 generations back. Meaning that an LTO-6 with read and write an LTO-5 tape and READ an LTO-4 tape. However, starting with LTO-8, the drives are only capable of reading and writing one generation back (meaning that an LTO-8 drive will not READ an LTO-6 tape).

The M8 entry for the LTO-8 drive refers to an LTO-8 drive using a specially formatted LTO-7 tape. Be aware that if you do have a system that will reformat your LTO-7 tapes to the 9TB, M8 format, those tapes cannot be reformatted back to LTO-7 format.

Finally, the LTO-M8 media (specially formatted LTO-7 tapes) store 9TB on an LTO-8 drive, but current LTO.org specs do not include reading M8 formatted tapes in an LTO-9 or later drive.

At this stage, with the lack of support moving to the planned LTO-9 spec, limited device support for manually formatting your own tapes, and the lack of an incremental capacity value, we do not recommend the M8 format as you only gain 3TB/tape and the cost per GB does not balance out against native LTO-8 tapes.

Tim
--
Tim Jones
CTO - TOLIS Group, Inc.
http://www.tolisgroup.com
BRU ... because it's the RESTORE that matters!


Return to posts index

Tim Gerhard
Re: LTO Tape Technologies update
on May 14, 2018 at 5:21:20 pm

+ LTO8 Full-Height is 360 MB/s on libraries. Was hoping IBM could do full height standalones, but they aren't playing ball.

I also agree M8 is horrible.

Tim Gerhard
MagStor Inc.
614-505-6333
tgerhard@magnext.com
NAB 2018 Booth #SL15816


Return to posts index

Luke Mullen
Re: LTO Tape Technologies update
on May 14, 2018 at 5:40:27 pm

You take a speed hit with half height standalone drives? How significant?


Return to posts index


Tim Gerhard
Re: LTO Tape Technologies update
on May 14, 2018 at 10:10:21 pm

You take a speed hit on half-height standalone or HH library drives on LTO8.

LTO4 and below was a bigger drop for half-height. I think LTO5 is when it was leveling out and you wern't getting any decrease up to LTO7s.

LTO1 even had 2x half heights with different speeds.

Tim Gerhard
MagStor Inc.
614-505-6333
tgerhard@magnext.com
NAB 2018 Booth #SL15816


Return to posts index

Tim Jones
Re: LTO Tape Technologies update
on May 15, 2018 at 10:09:23 pm
Last Edited By Tim Jones on May 16, 2018 at 12:19:32 am

Not on any drives since LTO-5. The servos and positioning controls are much more exact than on the older drives, so the tapes run at full speed on both.

As others have mentioned, the full height drives are specific to a group of IT-oriented silo-style libraries. So unless you're working with the big full rack, multi-cabinet units, there's no use for a full height drive.

Tim
--
Tim Jones
CTO - TOLIS Group, Inc.
http://www.tolisgroup.com
BRU ... because it's the RESTORE that matters!


Return to posts index

Tim Jones
Re: LTO Tape Technologies update
on May 15, 2018 at 10:14:14 pm

I suspect that you're probably seeing a difference between Fiber Channel and SAS more than FH versus HH. Fiber Channel doesn't suffer from the causes of the slow down on SAS due to TLR and buffer issues. You also won't see the slow down with SAS if you're using a 12Gb SAS HBA (which the Mac platform does not support - PCIe-3 x8)..

There really is no difference with the FH to HH comparison when the host environment is equal.

Tim
--
Tim Jones
CTO - TOLIS Group, Inc.
http://www.tolisgroup.com
BRU ... because it's the RESTORE that matters!


Return to posts index


Neil Sadwelkar
Re: LTO Tape Technologies update
on May 24, 2018 at 2:02:59 pm

For the purpose of calculation (and budgeting), I normally account for the 'overhead', particularly for file sequence type of data.

So, my numbers are
LTO-5 - 1.3 TB
LTO-6 - 2.2 TB
LTO-7 - 5.2 TB

This is from adding files/folders in 100 GB increments, and doing 'How many tapes' in Bru-PE till it goes from '1 LTO-x tapes' to '2 LTO-x tapes'.

-----------------------------------
Neil Sadwelkar
neilsadwelkar.blogspot.com
twitter: fcpguru
FCP Editor, Edit systems consultant
Mumbai India


Return to posts index

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
© 2018 CreativeCOW.net All Rights Reserved
[TOP]