5.3-RELEASE: SMP: system clock has died

O. Hartmann ohartman at uni-mainz.de
Tue Jan 11 06:01:10 PST 2005

UEMURA (fka. MAENAKA) Tetsuya schrieb:

>Posted on Sat, 08 Jan 2005 17:31:56 -0700
>by author Stephane Raimbault <segr at hotmail.com>
>>I have an ASUS P2B-DS motherboard with dual P2 400MHz CPU's.  I have 
>>compiled the SMP kernel and noticed that something is not right.  In "top" 
>>the CPU values indicate 0% across the board, even idle!
>I found 5 PRs regarding this symptom. On my 5.3-STABLE server, patch
>attached with PR 17800 solved the problem.
>For information, Tyan S1867DLUAN Thunder 2500 dual Slot 1 motherboard
>always shows correct CPU usage on FreeBSD 5.x since early 2003, its
>Socket 370 alternative S2567U3AN Thuder HEsl shows incorrect  on
>5.3-BETA4 and recent 5.3-STABLE without patch.
I also see the phenomenon, that 'systat -vmstat 1' show sometimes
'alternate system clock has died' on a ASUS CUR-DLS SMP system (dual 
This mainboard utilize the LE 3.0 RCC chipset (Socket 370 FCPGA).
SMP is risky on all flavours of FreeBSD 5.3 from BETA4 on!

I was told to have a faulty hardware, but I believe in a IRQ routing 
problem since the
machine does weird thing swapping NIC or add-on cards in the PCI slots 
or disabling
both serial ports (diabling both serial ports in the  BIOS remains each 
flavour of kernel,
UP or SMP, to be stuck after SCSI init and resetting (U160 built in SCSI)).

More information about the freebsd-smp mailing list