On 03/09/2012 01:43 AM, Adam Williamson wrote:
On Thu, 2012-03-08 at 22:19 -0700, Chris Murphy wrote:
I'm not sure how useful 'time' is as a benchmark for file copies.
Don't file transfers get cached and return to a console as 'complete'
long before the data is ever written, sometimes?
I'm pretty sure you sometimes hit the case where you copy 200MB to a USB
stick, it returns to the console pretty fast, but the light on the stick
is still flashing, and if you run 'sync', it sits there for quite a
while before returning to the console, indicating the transfer wasn't
really complete. So I'm not sure 'time'ing a 'cp' is an accurate test of
actual final-write-to-device.
That is true---but in that case, we could flush the disks. and then time
the operation followed by another flush, i.e.:
sync; time (cp ...; sync)
I assume that the old-time Unix superstition of calling sync three times
no longer applies :)
Perhaps a dedicated disk benchmark like bonnie++ would be a better test,
though.
--
devel mailing list
devel@xxxxxxxxxxxxxxxxxxxxxxx
https://admin.fedoraproject.org/mailman/listinfo/devel