Ok, so I bought a tape drive from ebay..its a Dell PowerVault 100T dds4 tape drive (internal seagate std1400lw). I really like the 4mm tape format because theyre so small. Just perfect for freezing my usual data output (some notes, documents).
At first I thought I bought a lemon, since the drive was super slow. As usual I played around with block sizes. Normally I leave the blocksize to 512, which is usually what I find tape drives to have the default set up as. I usually would do this:
mt -f /dev/st1 setblk 512 # if necessary
tar cvfp /dev/st1 ....
Or, sometimes, If I want the default tar blocking factor to be the same as the hardware block size:
mt -f /dev/st1 setblk 10240 # thats 20 tar blocks of 512 each
tar cvfp /dev/st1 ...
But the tape drive is SUPER SLOW no matter how I tried...Until I tried 4096 (page size?) on a whim. And this drive just flew! So this is how to make this drive spin fast:
mt -f /dev/st1 setblk 4096 # page size
tar cvfpb /dev/st1 8 ...
tar tvfb /dev/st1 8 .....
What a surprise that was.. and I was using tapes for years.
--------------UPDATE-------------
20190918
The slow speed is for READING BACK DATA, not writing them. For some reason the tape drive stalls delivering data for data transfers > 4k. Therefore, to read back data, specify transfer buffers of 4k or less:
mbuffer_style# mbuffer -s 4096 -i /dev/st2 | tar tvf -
normal_tar# tar xvfpb /dev/st2 8
JondZ 20190917
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