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From: Clemens Ladisch <clemens@ladisch.de>
To: Felix Homann <linuxaudio@showlabor.de>
Cc: alsa-devel@alsa-project.org
Subject: Re: Fast Track Ultra latency and new streaming logic.
Date: Thu, 03 May 2012 17:21:52 +0200	[thread overview]
Message-ID: <4FA2A290.6010301@ladisch.de> (raw)
In-Reply-To: <CAFz=ag7fvr5+Pz0jePNZ+7xhXZ7n1Td4v3=ZZFQcb6Sqy+RQXw@mail.gmail.com>

Felix Homann wrote:
> 2012/5/3 Clemens Ladisch <clemens@ladisch.de>:
>> USB playback also adds further latency by queueing the packets; the
>> number of packets can be seen under "URBs" in /proc/asound/card?/stream0.
>> (There are 1000/8000 packets per second at full/high speed.)
>
> I'm getting "URBs = 2 [ 5 6 ]"  for playback and  "URBs = 8 [ 8 8 8 8
> 8 8 8 8 ]" for capture with the "old" streaming logic. What does it
> mean?

The queue length is 5+6 = 11 packets; at high speed, that's
11 / 8 kHz = 1.4 ms.


Regards,
Clemens

  parent reply	other threads:[~2012-05-03 15:17 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-05-01  0:18 Fast Track Ultra latency and new streaming logic Grant Diffey
2012-05-01 13:09 ` Felix Homann
2012-05-02  8:41 ` Daniel Mack
2012-05-03  8:39 ` Felix Homann
2012-05-03 14:03   ` Felix Homann
     [not found]     ` <CAFz=ag4j2OZTZqzeo+h210AaVgToA93hTs5QPL1UPHCCCLJkZg@mail.gmail.com>
2012-05-09 13:12       ` Takashi Iwai
2012-05-09 18:13         ` Felix Homann
2012-05-09 15:07       ` Felix Homann
2012-05-03 14:13   ` Clemens Ladisch
     [not found]     ` <CAFz=ag7fvr5+Pz0jePNZ+7xhXZ7n1Td4v3=ZZFQcb6Sqy+RQXw@mail.gmail.com>
2012-05-03 15:21       ` Clemens Ladisch [this message]
  -- strict thread matches above, loose matches on Subject: below --
2012-05-08 17:07 Aurélien Leblond

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