From alsa-devel-owner@alsa.jcu.cz  Thu Jan 14 15:13:51 1999
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	Thu, 14 Jan 1999 15:12:57 +0100
Date: Thu, 14 Jan 1999 15:12:57 +0100 (CET)
From: Jaroslav Kysela <perex@jcu.cz>
To: Kerry Hoath <kerry@gotss.ml.org>
cc: alsa-devel@alsa.jcu.cz
Subject: Re: ISA DMA problems
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On Thu, 14 Jan 1999, Kerry Hoath wrote:

> This is just a qucik message to see if you got my message on the list about
> ISA DMA problems that I experience with Alsa drivers and more than 16m of ram,
> Was my diagnostic correct or am I missing something? I am no programmer,
> but I think I understand the problem with kernel memory fragmentation and the
> inability of the alsa modules to get dma-able memory below the 16-meg address
> space when the memory pool becomes fragmented.

This is kernel problem. You can get same trouble if you are using floppy
disk when memory is fragmented.

We can do some workarounds, of course. For example write one module which
should be loaded immediately after system boot and allocate some space for
requested number of DMA channels. Any other ideas?

							Jaroslav

-----
Jaroslav Kysela <perex@jcu.cz>
Academic Computer Centre, University of South Bohemia
Branisovska 31, C. Budejovice, CZ-370 05 Czech Republic


