“Are you running an Intel Linux system with at least one (E)IDE
hard drive? Wouldn’t it be neat if there were a magical command to
instantly double the I/O performance of your disks? Or, in some
cases, show 6 to 10 times your existing throughput? Did you ever
just wonder how to tell what kind of performance you’re getting on
your “tricked-out” Linux box?”
“So, you’ve got your brand-new UltraATA/66 EIDE drive with a
screaming brand-new controller chipset that supports multiple PIO
modes and DMA and the leather seat option and extra chrome… But
is your system actually taking advantage of these snazzy features?
The hdparm(8) command will not only tell you how your drives
are performing, but will let you tweak them out to your heart’s
content.”
“Now before you get too excited, it is worth pointing out that
under some circumstances, these commands CAN CAUSE UNEXPECTED DATA
CORRUPTION! Use them at your own risk! At the very least, back up
your box and bring it down to single-user mode before
proceeding.”