Feedback on benchmarking results of SDHCI and MMCCAM driver

[Russell Haley]

On Mon, May 14, 2018 at 4:18 PM, Russell Haley <russ.haley at gmail.com> wrote:

>
>
> On Mon, May 14, 2018 at 2:51 PM, Udit agarwal <dev.madaari at gmail.com>
> wrote:
>
>> On Tue, May 15, 2018 at 3:11 AM, Peter Jeremy <peter at rulingia.com> wrote:
>>
>> > On 2018-May-15 02:48:43 +0530, Udit agarwal <dev.madaari at gmail.com>
>> wrote:
>> > >I have conducted several sd card benchmarking tests on FreeBSD 11.1,
>> with
>> > >both SDHCI and the newly incorporated MMCCAM driver to compare their
>> > >performance under different conditions.
>> >
>> > Some questions:
>> > 1) How reproduceable are the results?  Have you performed the test
>> > multiple times
>> > to check for variance?
>>
> The images that Udit is using for his tests can be made available for
> verification if that's desirable (we have a webserver available). His blogs
> are very good as well.
>

Sorry, sent before adding the blog address: http://81.4.107.225/wordpress/


>
>
>
> >
>> Yes, i have carried these tests multiple time and the results are pretty
>> consistent upto 0.1MBPS.
>>
>> > 2) How did you prepare the SD card prior to each write test?  Flash
>> write
>> > tests
>> > are extremely sensitive to hidden move/rewrite and erase cycles
>> performed
>> > by the
>> > flash translation layer.
>> >
>> Before each test, I freshly recreated the filesystem to remove any trace
>> of
>> the previous tests. Moreover, I have mounted/unmounted the device  to
>> purge
>> any data in the cache.
>>
>> > 3) Have you tried different SD cards from different manufacturers to see
>> > if the
>> > drivers happen to interact well or badly with the specific flash
>> > implementation.
>> >
>> No, currently i havn't experimented with different sd cards. True, it
>> would
>> be interesting to figure out the interaction of the driver with different
>> flash implementations. I'll perform these tests ASAP.
>>
>
> I'll just point out that Udits SGOC project has nothing to do with the
> flash implementation of the cards. Udit, I would hesitate to go down the
> road of multiple card tests unless you have a great deal of spare time.
> There are far more pertinent questions that can be asked about the variance
> between SDHCI and SDIO implementations. There is still the little detail of
> porting to RTEMS too. :)
>
>
>> Regards,
>> Udit
>>
>> >
>> > --
>> > Peter Jeremy
>> >
>> _______________________________________________
>> freebsd-arm at freebsd.org mailing list
>> https://lists.freebsd.org/mailman/listinfo/freebsd-arm
>> To unsubscribe, send any mail to "freebsd-arm-unsubscribe at freebsd.org"
>>
>
>