Port-amd64 archive

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Old Index]

Re: boot fail with large RAM

Manuel Bouyer wrote:
On Wed, Nov 18, 2009 at 08:23:22PM +0100, Manuel Bouyer wrote:
I also noticed that amd64 has only 2 free lists, one for the low 16MB
memory and one for anything else. Would it help to move to a third
free list; one for low 16MB, a second for the low 4GB and a third one for
anything else ? uvm(9) doens't say much about free lists ...

I tried it; it helps a lot (see attached dmesg). The system can boot,
and devices seems to be working fine. I also tested it on a desktop with
8GB ram, and another one with 2GB.
I think this patch can also help systems which don't have troubles at
boot time but could end up with bus_dma(9) allocation failures at
run time. So unless someone objects I'm going to commit the attached
patch in the next few days, and request a pullup to netbsd-5.

Yep, your patch is the right thing to do. I remember considering this when I first did the amd64 port, but somehow it ended up on the backburner and I forgot about it.

The thing that is eating up all your low memory is probably VM page structures. With 128G, there are some 32M of them, so that counts for a lot (probably about 2.5G total).

- Frank

Home | Main Index | Thread Index | Old Index