
Create turbocharged storage using tmpfs - seancron
http://kevin.vanzonneveld.net/techblog/article/create_turbocharged_storage_using_tmpfs/
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georgebashi
I've seen this tip a few times before, but have always wondered: isn't this
what the OS disk cache should do? One of the "possible uses" is:

 _What if you're an internet host and you want to show off your massive
bandwidth by having users download a dummy .bin file of 100MB. You'll find
that if many users access this file at the same time, your hard drive becomes
the slow factor and you're running into disk IO problems._

Surely the OS should keep this 100MB around, rather than re-reading it from
the disk over and over? By keeping it in tmpfs, aren't you just "locking" the
file in RAM, and defeating whatever "optimal" choice the OS is making over
what files to keep around? Isn't this something better done by vmtouch?
(<http://hoytech.com/vmtouch/>)

~~~
wmf
Yeah, I don't see any reason why tmpfs would be faster than hitting in the
page cache (since that's what tmpfs _is_ ). Also, AFAIK tmpfs memory is
swappable, so it isn't even guaranteed to be in RAM.

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Adrock
As was already pointed out, you're often better off relying on the OS disk
cache.

One situation that I've had a good use for tmpfs was when watching videos on
my non-SSD-equiped laptop on a long flight. I'd copy the video to tmpfs and
then force the hard drive to spin down. It had a measurable impact on battery
life.

