Topic: SME 5.6 and Intel 845 Chipset

[Jason Scrivener]

Just wondering if anyone has found any solutions to the incompatibility problem between SME 5.6 and motherboards with the Intel 845 chipset on them?

[Jason]

Yes i went back to 5.5 update 2 and it works great.

[Michael]

Jason,

could you explain which incompatibility exists or where to find the details about it?
I can only add an incompatibility that we found for SME 5.5 already:
845 chipset with 1 x 512MB PC2x00 RAM module = runs extremly slow!
When you look at those times:
May 12 11:19:29 server1 kernel: raid5: MMX detected, trying high-speed MMX checksum routines
May 12 11:19:29 server1 kernel:    pII_mmx   :    21.336 MB/sec
May 12 11:19:29 server1 kernel:    p5_mmx    :    22.098 MB/sec
May 12 11:19:29 server1 kernel:    8regs     :    12.192 MB/sec
May 12 11:19:29 server1 kernel:    32regs    :     7.620 MB/sec
May 12 11:19:29 server1 kernel: using fastest function: p5_mmx (22.098 MB/sec)   <---!!!!!!!!!!!!!
which should look like that:
May 12 14:19:23 server1 kernel: raid5: MMX detected, trying high-speed MMX checksum routines
May 12 14:19:23 server1 kernel:    pII_mmx   :  2752.725 MB/sec
May 12 14:19:23 server1 kernel:    p5_mmx    :  2683.764 MB/sec
May 12 14:19:23 server1 kernel:    8regs     :  2798.064 MB/sec
May 12 14:19:23 server1 kernel:    32regs    :  1643.253 MB/sec
May 12 14:19:23 server1 kernel: using fastest function: 8regs (2798.064 MB/sec)  <----!!!!!!!!!!!!

I had the same results with PC2100 and PC2700 RAM modules but I have not tested yet 2 x 256MB modules to see whether that makes a difference.

Regards,
Michael

[Jason]

Basically i found a problem trying to load 5.6 on a intel 845 motherboard on two diffrent machines running 2 X 80gb hard drives in raid. one machine had 256mb pc2100 and the other had 512mb pc 2700 and both had the same problem of being very slow (in any hard drive accsessing situation). I then went back to 5.5 update 2 and no problem worked very fast. i have seen in the topics people having similar issues with 5.6 and 845 intel and hdd over 40gb running raid. By the way 5.6 worked ok without raid ie disconect one hard drive but in raid no go

[Charlie]

Jason Scrivener wrote:

> Just wondering if anyone has found any solutions to the
> incompatibility problem between SME 5.6 and motherboards with
> the Intel 845 chipset on them?

I've only personally met one such motherboard, and it worked fine with SME5.6 after I tweaked DMA settings (down to UDMA mode 2, IIRC) in the BIOS. Try that, and let us know how you get on.

Charlie

[Jason Scrivener]

I've done a bit of research into this problem and I think I have found the problem, and a working solution.

A quick search on RedHat's bugzilla site for any mention of the intel 845 chipset and hard disk related problems for RedHat 7.3 (what SME version 5.6 is based on) revealed the same problem at https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=67833

Basically, the kernel that ships with RedHat 7.3 (and therefore SME 5.6) is broken for the IDE controller with the 845 chipset.

The final comment reads:
rh 9.0 2.4.20-8 and 2.4.20-9 on inspiron 8500 do not correctly recognize ide
chip. The workaround is to install 2.4.18-27 from 8.0 distro (it works even on
9.0!) and call "hdparm -t1 /dev/hda" in /etc/rc.local

This indicates that the kernels distributed with RedHat 8.0 work ok with the Intel 845 chipset.

So, all we need to do is modify the boot disk and the SME install CD and replace the kernels with the versions from RedHat 8.0.

I created a boot floppy from the SME 5.6 CD, and then replaced the vmlinuz file on it with the one from a redhat 8.0 floppy.  The floppy boots fine, and the SME installation starts ok, however the install is broken because the kernel modules on the CD do not match the kernel version on the boot disk.  So we need to replace the kernel modules on the installation CD.  

The kernel modules live in modules.cgz which is in the file e-smith/base/stage2.img on the installation CD.  I mounted this image, copied the content, and replaced the modules.cgz file in it with the one from redhat 8.0.  I then made a new stage2.img file and made a new installation CD.  

At this point the installation ran fine - very fast.  But it still installed the 7.3 kernel onto the hard disk, so when the system rebooted off the hard disk, it was really slow.

I then replaced the following rpms on the installation cd with the redhat 8.0 equivalents.

kernel
kernel-pcmcia
kernel-smp
kernel-utils
modutils
mkinitrd
glibc
glibc-common
remove ucdsnmp and replace with netsnmp (The package has had a name change between Redhat 7.3 and 8.0).

I built a new install image, and the system installed and is running at full speed.  I have two 80Gb drives in a software RAID configuration, they took a couple of hours to sync (as opposed to days with the original installation cd), and have remained sync'd through reboots and power cycles.  I have applied update 4 to the server without an issue, and copied around 7Gb to and from it to test IO throughput.  It's all working fine.  Running hdparm on both the hard disks shows DMA is enabled and in use.

So the bug in SME appears to come from RedHat 7.3 - the shipped kernel does not support the Intel 845 chipset properly.

Jason.

[adonis]

I'm having the same problem with intel 845 chipset and i've tried Jason soluion.

I want to ask how you can fit vmlinuz from redhat 8 boot disk into sme boot disk.
Total size is more than 1.44 Mb since initrd for sme is  larger that the redhat's one and both total a size more than 1.44MB


Please help!.

[adonis]

I'm having the same problem with intel 845 chipset and i've tried Jason soluion.

I want to ask how you can fit vmlinuz from redhat 8 boot disk into sme boot disk.
Total size is more than 1.44 Mb since initrd for sme is  larger that the redhat's one and both total a size more than 1.44MB


Please help!.

[Charlie]

adonis wrote:

> I'm having the same problem with intel 845 chipset and i've
> tried Jason soluion.

Have you tried my proposal [Tweak the BIOS settings]? Much quicker to try, and you can still upgrade the kernel later if you wish (but be warned, the RH kernel doesn't support PPTP at all).

Charlie

[adonis]

re: Charlie

I tried your recomentations for bios tweaking but does not seem to work for me.
I rollback to sme 5.5 and works ok, but it seems that 5.5 can not handle hdd more
that 140GB. I am using 2XWD 200GB drives in softraid and need arount 32 hours
to synchronise, but size is reported as 130GB for the array.