Re: Very slow transfers to/from micro SD card on a RPi B+

[Sujit K M <sjt.kar%gmail.com@localhost>]

On Thu, Jul 9, 2015 at 4:35 PM, Stephan <stephanwib%googlemail.com@localhost> wrote:
> Well, you can finde a previous discussion here:
>
> http://mail-index.netbsd.org/tech-kern/2014/08/22/msg017539.html

As per this mail chain, you were trying to use dtrace to find the bottle neck.

>
> The point was that creating many (even empty) files leads to a very high
> kernel CPU consumtion along with almost no disk activity. What happens
> behind the scenes is still unknown to me. One should check whether WAPBL
> makes a difference here (mount option "log" enables WAPBL journaling). It
> might be helpful to have DTrace working in order to investigate this.

I Feel it is because of the Processor Speed more than any thing else, could you
post cpuinfo, might be of help. Below a bench mark on i5, I think it
generally summarizes
it to be because of processor speed.

http://www.tomshardware.com/charts/microsd-cards-2014/benchmarks,169.html