From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stas Sergeev <stsp@aknet.ru>
Subject: Re: underruns and strange code in pcm_rate.c (and
	patch)
Date: Thu, 08 Nov 2007 12:13:29 +0300
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To: Takashi Iwai <tiwai@suse.de>
Cc: alsa-devel@alsa-project.org
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Hello.

Takashi Iwai wrote:
> Not really.  It checks appl_ptr of the client, not hw_ptr.  appl_ptr
> is what app writes.  So, as long as app writes only the period size,
> the hack isn't triggered.
No, its not that simple.
When the partially filled period
on slave appears, it then gets
populated back. Namely, snd_pcm_write_areas()
takes it via snd_pcm_avail_update().
It then adjusts the "frames" accordingly,
and then also "size" gets infected.
Then the hack triggers.