Skip site navigation (1)Skip section navigation (2)
Date:      Thu, 27 Sep 2001 17:29:33 -0400 (EDT)
From:      <joeo@cracktown.com>
To:        <freebsd-multimedia@freebsd.org>
Subject:   stable pcm problem with some linux games errs apps
Message-ID:  <Pine.LNX.4.30.0109271710530.12814-100000@asmodean-ssn.nks.net>

next in thread | raw e-mail | index | archive | help
A few of the games from Loki use the OpenAL libs to drive sound.  PCM on
my 4.4-RC4 box is displaying a long standing (I've kindof ignored it for
the last year) problem that games like UT and Tribes2 of noticable lag in
sound compared to what is seen on a linux box.  The lag is much less
noticable if I use the 4-front tech OSS driver.

Setting up some debugging reveals that both these games do a ioctl
DSP_SETFRAGMENT requesting only 1 DMA block.

Here's what UT requests;

SNDCTL_DSP_SETFRAGMENT 0x0001000b
SNDCTL_DSP_SETFRAGMENT 1 frags, 2048 sz
SNDCTL_DSP_SETFRAGMENT 0x0001000c
SNDCTL_DSP_SETFRAGMENT 1 frags, 4096 sz

I was hoping that the workaround for would be a simple kluge, but
chn_setblocksize(...) in /sys/dev/sound/pcm/channel.c has some additional
logic in it that sets the blkcnt much higher...

Any ideas?


To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-multimedia" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?Pine.LNX.4.30.0109271710530.12814-100000>