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Date: Tue, 25 Jan 2011 12:05:43 +0100
From: Gerd Hoffmann <kraxel@redhat.com>
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Subject: Re: [Qemu-devel] [RESEND PATCH 2/3] pulseaudio: setup buffer attrs
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To: qemu-devel@nongnu.org

   Hi,

> What's the default buffer size?

Don't know the exact number, but pulse's default buffer size is quite 
big by design.  Which is fine for most apps (such as mp3 players) where 
loading more sound data into the buffer every second or so is ok.  It 
doesn't work very well for sound card emulation though.  And it doesn't 
work at all if your guest happens to use a ring buffer which holds sound 
data for only 20ms.

 > Is there any reason to query this on startup
 > somewhere instead of hard coding it?

No.  The pulse default values will never ever work for qemu's low 
latency requirements.

cheers,
   Gerd