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Re: unscientific eMMC read speed test

 

On Mon, Sep 26, 2011 at 22:04, Leon Romanovsky <leon@xxxxxxx> wrote:
> On Mon, Sep 26, 2011 at 19:35, Jani Monoses <jani.monoses@xxxxxxxxx> wrote:
>> On Mon, Sep 26, 2011 at 3:00 PM, Jani Monoses <jani.monoses@xxxxxxxxx>
>> wrote:
>>>
>>> 10Z model with kernel built from current git (not a deb package install)
>>> and no modules loaded.
>>> 4294967296 bytes (4.3 GB) copied, 160.107 s, 26.8 MB/s
>>> 0.02user 24.74system 2:40.12elapsed 15%CPU
>>> I need to see why I have worse numbers with the .deb
>>
>> So if I boot with a kernel and modules moved out of the /lib/modules path so
>> it cannot find them on boot,
>> the speed is 26/27 MB/s
>> If I boot same kernel and allow modules to load (37 of them) the speed is
>> 16/17 MB/s .
>> Loading in all those modules in a kernel that started without them does not
>> affect the performance, it remains at 26Mb
>> Loading them at boot seems to have an effect on how the system behaves
>> later.
>> Jani
> leon@ssd:~$ sudo dd if=/dev/mmcblk0 of=/dev/null bs=4M count=1024
> 1024+0 records in
> 1024+0 records out
> 4294967296 bytes (4.3 GB) copied, 264.54 s, 16.2 MB/s
> leon@ssd:~$ uname -a
> Linux ssd 2.6.38.3+ #29 SMP PREEMPT Sat Sep 24 13:54:54 IDT 2011 armv7l armv7l
> armv7l GNU/Linux
>
> Kernel based on latest commit cbc11bee6315a98c65dd18e4b1b8559328a468e2
> With modules loaded at the boot.
Forgot to mention: AC100-118


>
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>
>
>
> --
> Leon Romanovsky | Independent Linux Consultant
>         www.leon.nu | leon@xxxxxxx
>



-- 
Leon Romanovsky | Independent Linux Consultant
        www.leon.nu | leon@xxxxxxx


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