On Thu, Sep 25, 2008 at 02:46:06PM -0700, Paul Goyette wrote:
at last for i386; never tested it on amd64.
I use
options PHYSMEM_MAX_ADDR=4096
on my amd64 with k8GB and it avoids numerous random crashed that I'd
been having.
I was told at one point that there was a problem with bounce buffers
over the 4GB limit, but then was told that that problem didn't exist.
So, I'm not sure what the actual problem is, but limiting to 4GB does
avoid the crashing.
There are no general issues with bounce buffers, AFAIK. But there
may be issues with individual drivers not doing the bus_dma(9)
thing properly.