Scyld with 2.4 kernel?
weller at zyvex.com
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 kernel.org, 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)
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 zyvex.com cell: (214) 616-6340
Zyvex Corp., 1321 N Plano facsimile: (972) 235-7882
Richardson, TX 75081 icq: 6180540
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