====== hdparm ======

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Attention, **hdparm** permet pas mal de choses mais il possède des options vraiment risquées... Agissez précautionneusement!
</WRAP>

Pour tester la vitesse de lecture d'un disque dur : 

<code bash>
$ sudo hdparm -Tt /dev/sda

/dev/sda:
 Timing cached reads:   14264 MB in  2.00 seconds = 7147.31 MB/sec
 Timing buffered disk reads: 332 MB in  3.01 seconds = 110.47 MB/sec

$ sudo hdparm -Tt /dev/nvme0n1

/dev/nvme0n1:
 Timing cached reads:   11248 MB in  2.00 seconds = 5634.97 MB/sec
 Timing buffered disk reads: 3026 MB in  3.00 seconds = 1008.22 MB/sec
</code>

===== Options dangereuses =====
Dans le [[man]] d'hdparm, on trouve des options qui font presque peur, par exemple :
<code bash>
       --drq-hsm-error
              VERY  DANGEROUS,  DON'T EVEN THINK ABOUT USING IT.  This option causes hdparm to issue an
              IDENTIFY command to the kernel, but incorrectly marked as  a  "non-data"  command.   This
              results  in  the  drive being left with its DataReQust(DRQ) line "stuck" high.  This con‐
              fuses the kernel drivers, and may crash the system immediately with  massive  data  loss.
              The option exists to help in testing and fortifying the kernel against similar real-world
              drive malfunctions.  VERY DANGEROUS, DO NOT USE!!
</code>