Hard drives
From ThorxWiki
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== Thrash the drive == |
== Thrash the drive == |
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| − | Drive thrashing should involve the looping creation (write) and md5sum (read) and then deletion of files of random sizes. Data from /dev/urandom. |
+ | 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? |
+ | * Is this efficient really? Do we need random filesizes? How about a range of constant sizes? Or just constant sizes? |
| + | == Destructive testing == |
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| + | Test a drive and then stress it till the tests break. Keep going till the drive breaks... |
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| − | == [[Magnets]] == |
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| − | |||
| − | What I have never seen is testing of magnets on drives. Now, I have alot of nice strong rare-earth magnets (from hard drives), and I have some old drives which are all but ready to be decomissioned. |
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| − | === Testing external magnetic effects on [[Hard drives]] === |
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# setup computer with an OS and boot drive. |
# setup computer with an OS and boot drive. |
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# attach drive-to-test |
# attach drive-to-test |
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# format drive |
# format drive |
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| − | # write data, md5sum written data |
+ | ## consider two partitions, then read/write files on both to observe :D |
| − | # bring magnets to drive |
+ | # write data, md5sum written data (/dev/zero, or urandom data? Random size or predictable size? predictable sized zero data can have pre-known md5sums) |
| + | # apply test |
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# md5sum data again to check against bit corruption |
# md5sum data again to check against bit corruption |
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# consider 'spamsum' to check for how MUCH of the data is corrupted. |
# consider 'spamsum' to check for how MUCH of the data is corrupted. |
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| − | * consider applying all this in a loop which runs constant, generating files (/proc/partitions), md5sum, wait for magnets, md5sum again, delete and repeat |
+ | * consider applying all this in a loop which runs constant, generating files (/proc/partitions), md5sum, test, md5sum again, delete and repeat |
* 10meg files? |
* 10meg files? |
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| + | |||
| + | === [[Magnets]] === |
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| + | I have alot of nice strong rare-earth magnets (from hard drives...) |
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* test for effects of magnetic field when writing files as well as reading |
* test for effects of magnetic field when writing files as well as reading |
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* test the effect of a moving magnetic field, vs a static one (as applied both before and after a format of the drive?) |
* test the effect of a moving magnetic field, vs a static one (as applied both before and after a format of the drive?) |
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| − | + | === foreign materials === |
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| − | == foreign materials == |
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* open breather hole, apply smoke |
* open breather hole, apply smoke |
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** thrash drive - how long till observable issues? |
** thrash drive - how long till observable issues? |
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| − | * open breather hole, but apply coke (alternate: drill hole) |
+ | * open breather hole, but apply liquid (water or coke) |
** will it seize up the drive? Or froth up the coke? |
** will it seize up the drive? Or froth up the coke? |
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| + | * Drill hole - shavings do what now? |
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* sparkler (inverted, through pre-drilled hole) |
* sparkler (inverted, through pre-drilled hole) |
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| + | * spray paint (after opening drive)** chalk spray |
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| + | ** metallic spray |
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| + | ** apply soot |
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| − | == Open drive == |
+ | == let's get physical... == |
| + | * hit drive with a hammer (rubber, then metal) |
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| + | * drop drive (in as far as is possible when attached to cables) |
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* open drive entirely... :) |
* open drive entirely... :) |
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| − | ** create two partitions, then read/write files on both to observe :D |
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| − | ** apply soot to drive platters, then see patterns with head movement... |
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Revision as of 15:01, 6 June 2014
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Measuring drive performance
- A basic Linux utility to measure drive latency and throughput, and record these continuously.
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...
- setup computer with an OS and boot drive.
- attach drive-to-test
- format drive
- consider two partitions, then read/write files on both to observe :D
- write data, md5sum written data (/dev/zero, or urandom data? Random size or predictable size? predictable sized zero data can have pre-known md5sums)
- apply test
- md5sum data again to check against bit corruption
- 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... :)
