FORUMS: list search recent posts

LTO-6 tape for archiving | BRU PE speed & computer requirements

COW Forums : Storage

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
Kiki Muchtar
LTO-6 tape for archiving | BRU PE speed & computer requirements
on Feb 19, 2015 at 8:49:46 am

Hi guys,

One of my job is to save digitized 35mm film to LTO-6 tape. I use an iMac 1.4GHz dual-core i5 w/Thunderbolt1, HP StoreEver LTO-6 Ultrium 6650, ATTO Thunderlink SH1068. My HDD source is an external HDD LaCie d2 Thunderbolt 2.

I'm on BRU PE trial now. It took 5 hours 15 minutes to complete archiving a 2TB folder (from LaCie disk to LTO tape), then it took the same time to verify it. (1) Is this a normal speed for both process, 5 hrs each?

Once I was using BRU PE to save another 2TB folder to LTO, and I also opened Word, Excel, PowerPoint with heavy graphics, the BRU PE was crashed. (2) Can I do something else when I'm archiving without interrupting the archiving process?

If we plan to have another computer designated solely for archiving, (3) which aspect will affect on archiving speed, the connection or the processor? I have two options:

Mac Mini 2.3Ghz quad-core i7 w/ Thunderbolt port
or
Mac Mini 1.4GHz dual-core i5 w/ Thunderbolt 2 port

Will be grateful to have your advice.

Thanks,
Kiki


Return to posts index

Bob Zelin
Re: LTO-6 tape for archiving | BRU PE speed & computer requirements
on Feb 20, 2015 at 1:01:06 pm

what you are observing is the INSANELY long time it takes to archive, and if you archive and verify, it's even longer. This is why many people HATE LTO tape technology. It's not the BRU software - it's the nature of LTO, and it has always been this way. Any other software, any other product would take this long.In these days of SSD drives, you observe LTO tape speeds, and generally say "are you kidding me". This is every product.

Some people try to plug in an LTO drive directly into their shared storage server, and suffer the same problems that you are observing, if they are trying to use the server for shared storage while they are making an LTO.

Get the i7 Mac Mini.

Bob Zelin

Bob Zelin
Rescue 1, Inc.
bobzelin@icloud.com


Return to posts index

Aaron Star
Re: LTO-6 tape for archiving | BRU PE speed & computer requirements
on Mar 15, 2015 at 2:36:28 am
Last Edited By Aaron Star on Mar 15, 2015 at 2:55:13 am

I used to handle tape back up for companies to LTO and DLT. The thing about tape backup you need to consider is that it is very much like writing CD/DVD media. Your host system and needs to be able to supply about 2x 160MB/s, in order to be able to keep up with the tape drive. Once your buffer is under-run to the tape media, the tape stops, backs up, and then continues writing. this repeats until your job is complete. At tape speeds, this eqauls large amounts of time cumulativly. If you want to improve this time, you need someone that can optimize your system down to the motherboard level. My guess is the host system cannot keep with the IO necessary to keep the tape streaming both in read and write mode. The ATTO device might be a bottle neck, or the external drive, each device in the chain need to be verified that it can perform at 300MB/s. Just because its a MAC+thunderbolt+"it works" doesn't mean its any where near optimized.

Even optimized to the point of keeping the tape streaming, the math works out to about 3.5 hours at 160MB/s to write 2TB. Verification is just that, it reads the entire tape back bit for bit, for and 3.5 hours. There is rarely any compression benefit when backing up video formats to tape, disabling compression on the drive could improve streaming.


Return to posts index

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
© 2017 CreativeCOW.net All Rights Reserved
[TOP]