Scyld with 2.4 kernel?

Mike Weller weller at
Fri Jun 15 14:35:51 PDT 2001

Does anyone know when Scyld plans on releasing their OS based 
on the 2.4 kernel?

On May 9, Sean mentioned that they were working on a new release.

I would like to have the 2.4 kernel for a couple reasons... I heard
that it had more efficient networking, Gaussian was more stable running
under 2.4 than 2.2 (according to someone on the list), and bigmem
support was builtin.

Since our nodes each have 1.5G of RAM, I was upset to find out that
the OS only saw 1G of RAM, whereas I saw 1.5G when I was using an
unmodified Redhat 6.2.  It turns out from looking at Scyld's kernel
source, they removed "bigmem" support, which I had to put back in by
recompiling the kernel.  Apparently, they used RedHat 6.2, took
the 2.2.17 kernel from, and then applied a lot of the
RedHat 7.0 patches to it, along with their "homebrew" patches.

My question is - why was bigmem support removed?  Were there stability
issues?  Due to subtle line-shifts in the kernel source from 2.2.16 (RH 7)
to 2.2.17, I had to manually patch a few files by locating the
code to be changed.

Here's a list of modifications that I did to Scyld's kernel
Summary of working kernel:

Patches obtained from REDHAT 7's:
linux-2.2.16-rawio.patch (RH 7)  - manual change to init/main.c
linux-2.2.16-iobuffix.patch (RH 7)
linux-2.2.16-raw-fixup.patch (RH 7)
linux-2.2.16-raw-fixup2.patch (RH 7)
linux-2.2.16-sigio.patch (RH 7)
bigmem-2.2.18pre2-18.bz2 (
tches/v2.2/2.2.17/) - manual change to mm/memory.c
linux-2.2.16-bigmem-dcache.patch (RH 7)
linux-2.2.16-bigmem-raw.patch (RH 7)
linux-2.2.16-bigmem-initrd.patch (RH 7)

The nodes appear to see it all now:
root at beowulf /etc/beowulf # bpsh -a free | egrep "Mem"
Mem:       1572388     980880     591508          0     841460      29148
Mem:       1572388     980848     591540          0     841392      29412
Mem:       1572388     981148     591240          0     841520      29580
Mem:       1572388     981564     590824          0     851992      17692

Michael J. Weller, M.Sc.               office: (972) 235-7881 x.242
weller at                         cell: (214) 616-6340
Zyvex Corp., 1321 N Plano           facsimile: (972) 235-7882    
Richardson, TX 75081                      icq: 6180540

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