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

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

Stephan

On Fri, Jul 10, 2015 at 5:43 PM, Sujit K M <sjt.kar%gmail.com@localhost> wrote:
> 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.

It would be nice if you could share us the status of this. Would be
very helpful,
If you have scripts ready.

>>
>> 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

https://en.wikipedia.org/wiki/Instructions_per_second

Please compare i5 with RPi b+.

-- 
-- Sujit K M

blog(http://kmsujit.blogspot.com/)