[alsa-devel] Period time/size in adaptive USB - alignment to nrpacks?

Pavel Hofman pavel.hofman at ivitera.com
Sun Jan 1 18:01:16 CET 2012

On 29.12.2011 09:43, Clemens Ladisch wrote:
> Pavel Hofman wrote:
>> Now please see the wireshark screenshot at
>> http://personal.educity.cz/dustin/wireshark.png . Frame 1197 is the last
>> URB of the period, with 960 bytes only. Yet the time distance around it
>> is again 8 ms (12.808-12.816-12.824). The expected 5 ms lag appears 2
>> URBs later, between frames 1201 and 1203 (12.832-12.837), all holding
>> 1536 bytes.
> Wireshark shows the URBs when they are submitted, which
> is in the completion handler of some previous URB.
> This means that the timing of the submission has no
> relation with its size.

Hi Clemens, thanks a lot for the clarification. Everything seems to be 
all right and verified :-)

Best regards,


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