utz lehmann [xfs@xxxxxxxxxx] wrote:
> Hi Seth
> Seth Mos [knuffie@xxxxxxxxx] wrote:
> > The dell PE 2500 is ServerWorks LE based, 2GB ram with both 2.4.10 and
> > 2.4.11-pre3.
> > The only way to fix it is not using HIGHMEM. As soon as I compile without
> > HIGHMEM (4GB) the box is stable and does not deadlock or crash even under
> > heavy load. I have about a month before the system must go into production
> > so if anyone has some hints or tests I could do they are most welcome.
> > I can not get it over my heart to tell that we cannot use half the
> > memory available. There goes my reputation :-/
> Maybe I have a solution for you (and others).
> I found a patch (linux-2.4.2-vm-1-2-3-gbyte.patch) in the redhat kernel src
> rpm. It allow you to change the standard vm user/kernel split of 3/1 GB to
> 2/2 and 1/3 GB. Without a HIGHMEM kernel your max available memory is kernel
> spilt size - 128MB. 896MB default, and 1920 or 2944MB with the patch.
> At work we have athlon based CAE workstations and numbercruncher with 1GB or
> 1.5GB RAM. They running 2.4.7 or 2.4.9 linux-xfs kernels (of course .-) with
> this patch. I modified the patch to 2.75/1.25 resp. 2.25/1.75GB. So they can
> use all their memory without HIGHMEM.
> Advantages are no performance loss due HIGHMEM and *NO* HIGHMEM trouble.
> Disadvantage is that the possible userspace size per process is reduced.
> If you don't have big processes it won't be a problem. I saw >1GB sized
> processes with the 2.25/1.75GB split.
> hope that helps.
Please note that I haven't used this patch with 2.4.10. It maybe break
things due the new vm.