From mboxrd@z Thu Jan  1 00:00:00 1970
From: Clemens Ladisch <clemens@ladisch.de>
Subject: Re: ALSA processor usage is too high
Date: Fri, 05 Nov 2010 15:31:04 +0100
Message-ID: <4CD41528.1060600@ladisch.de>
References: <AANLkTik-sb1OihaDhNgptH44gQ4__E+ozxhSKpA9GdSK@mail.gmail.com>
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To: Adam Rosenberg <adam@alcorn.com>
Cc: alsa-devel@alsa-project.org
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Adam Rosenberg wrote:
> I am trying to decode 8 MP3 files simultaneously.  Each file is 3
> minutes 11 seconds long.  When I just decode the files and copy the
> PCM data to memory it takes 2 minutes 36 seconds.  When I do the same
> test after opening 8 ALSA PCM streams and while writing data to them
> it takes 4 minutes 37 seconds.  This is much too slow for what should
> be a simple copy operation.

Are you using the "hw" device?  Otherwise, it's not a simple copy op.

How much CPU does "aplay -D hw -t raw -f dat /dev/zero" use?


Regards,
Clemens