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Recent Sales Hint That Tape For Storage Is Far From Dead
hightechchick writes "Staples' business-to-business sales of backup tape for storage are experiencing a bit of a revival. What's next, a return to dumb terminals and mainframes (a la cloud computing)?"
The business I work for goes through tapes like they're used to make coffee. Primary use: legal escrow of source code.
Yep, but that's what it takes to keep it running above minimum speed, writing a single large filesystem volume takes longer than writing 4 volumes almost as large because the drive shoeshines with a single job. Minimum rate for the drive is 40MB/s, the best I have done with tuning on a 72 drive vraid6 volume is 35MB/s and average is closer to 25MB/s sustained but 4 jobs from the same array on different volumes will give me 100-120MB/s. All volumes are spanned across all disks so it's not a matter of more spindles being available, it's the latency in all the metadata lookups.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
Points in favour of tapes:
- most backup software is designed to deal with tape libraries, not so much with shuffling B2D media around
- most archive companies are built around storing tapes; though I suspect there are ones which could deal with hard disks in external caddies
- tapes deal with stress from being transported continuously better than mechanical drives (also wear and tear of plugging and unplugging the interfaces all the time)
- I think unused tapes age better than unused hard disks, but I've nothing to back that up
Bandwidth to the tape drive itself rarely seems to be an issue for actual backups, since network and file I/O latency seem to be more significant issues. We never get anywhere near the maximum speed out of our LTO-4 drive, even when we're just duplicating data from the local array to the tape.