From mboxrd@z Thu Jan 1 00:00:00 1970 From: Takashi Iwai Subject: Re: Memory allocation and the "prealloc" procfile Date: Tue, 05 Apr 2005 19:16:39 +0200 Message-ID: References: <1112605417.6910.26.camel@andys_dellm60.ss82amr.net> Mime-Version: 1.0 (generated by SEMI 1.14.5 - "Awara-Onsen") Content-Type: text/plain; charset=US-ASCII Return-path: In-Reply-To: <1112605417.6910.26.camel@andys_dellm60.ss82amr.net> Sender: alsa-devel-admin@lists.sourceforge.net Errors-To: alsa-devel-admin@lists.sourceforge.net List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , List-Archive: To: Andy Robinson Cc: ALSA devel List-Id: alsa-devel@alsa-project.org At Mon, 04 Apr 2005 10:03:37 +0100, Andy Robinson wrote: > > I'm using Mandrake 10.1 on a DELL Precision M60. > Soundcard is Intel 82801DB-ICH4 > ALSA version 1.0.6 > > By default, /proc/asound/card0/pcm0p/sub0/prealloc contains the number > 64 and SNDCTL_DSP_GETOSPACE reports a total of 16k bytes output space > available. If I > echo 128 >/proc/asound/card0/pcm0p/sub0/prealloc > then SNDCTL_DSP_GETOSPACE reports a total of 32k bytes. > > My question is, what is the rest of the "prealloc" memory being used > for? And how can I change the amounts used for whatever other purposes, > so as to get a bigger SNDCTL_DSP_GETOSPACE buffer? It's not such a > problem for me but one of my users reports that with a 128k "prealloc", > he still gets only 4k from SNDCTL_DSP_GETOSPACE. Is it perhaps an ALSA > version issue? It might be. It's worth to try the latest ALSA version, anyway. If you want a bigger buffer, you can call SNDCTL_DSP_SETFRAGMENT ioctl to specify the fragments and its size explicitly. Takashi ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click