On 07/13/15 19:38, jd1008 wrote:
On 07/13/2015 05:15 PM, Patrick O'Callaghan wrote:
<<>>
IIRC USB drives are not DMA driven, i.e. each filesystem block written to the drive has to be pushed over the serial bus and handled by the CPU. Also, check if the drive is mounted with the 'flush' option, which sacrifices speed for greater integrity (i.e. less damage of the user pulls the drive without ejecting it).
poc
Good tip. I will check next time when I rerun the test.
i agree with 'poc' 100% with both of his statements.
also, i think you might want to rethink your thinking.
you say you are connecting to a usb2 port and device is a usb3.
near all reading of spec for usb3 devices that will work on usb2 have a statement that thru put speeds will be less if used on usb2.
more for thought, is tar building finale file in memory, /tmp, or on the usb3 drive?