Hard drives

Measuring drive performance

• A basic Linux utility to measure drive latency and throughput, and record these continuously.
  • http://www.coker.com.au/bonnie++/readme.html
  • http://linuxappfinder.com/utilities/benchmarks

Thrash the drive

Drive thrashing should involve the looping creation (write) and md5sum (read) and then deletion of files of random sizes. Data from /dev/zero

• Is this efficient really? Do we need random filesizes? How about a range of constant sizes? Or just constant sizes?

Destructive testing

Test a drive and then stress it till the tests break. Keep going till the drive breaks...

1. setup computer with an OS and boot drive.
2. attach drive-to-test
3. format drive
   1. consider two partitions, then read/write files on both to observe :D
4. write data, md5sum written data (/dev/zero, or urandom data? Random size or predictable size? predictable sized zero data can have pre-known md5sums)
5. apply test
6. md5sum data again to check against bit corruption
7. consider 'spamsum' to check for how MUCH of the data is corrupted.

• consider applying all this in a loop which runs constant, generating files (/proc/partitions), md5sum, test, md5sum again, delete and repeat
• 10meg files?

Magnets

I have alot of nice strong rare-earth magnets (from hard drives...)

• test for effects of magnetic field when writing files as well as reading
• test the effect of a moving magnetic field, vs a static one (as applied both before and after a format of the drive?)

foreign materials

• open breather hole, apply smoke
  • thrash drive - how long till observable issues?
• open breather hole, but apply liquid (water or coke)
  • will it seize up the drive? Or froth up the coke?
• Drill hole - shavings do what now?
• sparkler (inverted, through pre-drilled hole)
• spray paint (after opening drive)** chalk spray
  • metallic spray
  • apply soot

let's get physical...

• hit drive with a hammer (rubber, then metal)
• drop drive (in as far as is possible when attached to cables)
• open drive entirely... :)