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Comment by basicplus2 | Hacker News Reader

"As for transfer speeds, they can reach 300MBps"

I am getting over 500MBps on my setup

Impressive.

Will you share more information about the specific details (i.e. hardware and configuration) for the set up you're running with?

well probably with compression

I wonder if the 300MBps figure might also be with compression.

No, the LTO-7 transfer speed is 3 Gb/s a.k.a. 300 MB/s without compression. The compression in drive may be useful for automated backups, but if you use the tape for an archive of files selected by yourself, it is better to disable the drive compression. If you have compressible files, you can compress them with better algorithms on the computer, before storing them on the tape.

> you can compress them with better algorithms on the computer

is that always true? what if I have dozen's of pdf's which are similar and compressed (most pdfs are)? wouldn't de-duplication also reduce the size? I mean with millions/billions/trillions of files of the same format.

For example on a computer you can use algorithms like lrzip, which search for very long distance redundancies (i.e. not in small data windows like traditional algorithms). This usually achieves a decent compression even on normally incompressible files, e.g. on collections of movies or on collections of PDF files, because it may find repetitions at least e.g. in the headers of the files or of the file sections. If there are similar files, then there are chances that lrzip will find repetitions between files, even if a traditional compression would not find repetitions inside a single file. If de-duplication is possible, then that would also be much more efficient than enabling the compression option of the tape drive.

Ok now i am embarressed.. I was out by factor of 10...

i am getting 50Mbps.. copying NAS to tape

For what its worth..

Network Router: TG789vas v2

NAS: Synology DS1815+

Switch: (for Server, Tape Drive, Tape Library & Their Associated UPS ) Airpho Gigabit AR-GS108

Server: X3650 M3 Running Windows 2012 R2

Tape Library: IBM TS3100 3573 L2U

Tape Drive: IBM LTO6 8Gib Fibre Channel 35P1624 Feature Code 8348

Tape Drive Fibre Channel Card: Avago AFBR-57F5PZ

Server Fibre Card: Emulex LPE12002

Using NO compression

I understand the new IBM LTO 8 Drives can get up around 750 to 800Mbps

Mind sharing the details of your setup? Interested in doing something similar.

I have been using since 2016 the following setup:

1. QUANTUM LTO-7 Tape Drive, Half Height, Tabletop 2. Delock Cable Mini SAS HD SFF-8644 > Mini SAS SFF-8088 1 m 3. LSI LSI00343 SAS 9300-8E Host Bus Adapter (8-Port, PCI-e 3.0 8x, SAS 3.0)

Also, there is a couple of useful tape accessories:

4. Cleaning Cartridge (I use one from Quantum) 5. Cases for storing LTO Ultrium cartridges (I use some from Turtle Case, for 20 cartridges each)

I forgot to mention that the files that are written to tape should come from an SSD, because an HDD is not fast enough. The files can come from an SSD of a remote computer, if you use 10 Gb/s Ethernet, as that is fast enough.