FreeBSD 8.0, Intel Xeon E5530, Dell R410, only 2 cores available

[John Baldwin]

On Friday 29 January 2010 6:28:17 pm Hoang V.D. | Creative Solutions GmbH 
wrote:
> Hello,
> 
> We just purchased a Dell PowerEdge R410 server with this CPU: Intel Xeon 
Processor E5530
> 
> http://ark.intel.com/Product.aspx?id=37103
> 
> According to specs the CPU has 4 cores, 8 Hyper-Threading threads, however 
after installing 
> FreeBSD 8.0 (amd64), only 2 cores (4 SMT threads) were recognized by the 
kernel. Here is the
> relevant dmesg extract:
> 
> -----------------
> Copyright (c) 1992-2009 The FreeBSD Project.
> Copyright (c) 1979, 1980, 1983, 1986, 1988, 1989, 1991, 1992, 1993, 1994
>         The Regents of the University of California. All rights reserved.
> FreeBSD is a registered trademark of The FreeBSD Foundation.
> FreeBSD 8.0-RELEASE-p2 #0: Tue Jan  5 21:11:58 UTC 2010
>     root at amd64-builder.daemonology.net:/usr/obj/usr/src/sys/GENERIC
> Timecounter "i8254" frequency 1193182 Hz quality 0
> CPU: Intel(R) Xeon(R) CPU           E5530  @ 2.40GHz (2394.01-MHz K8-class 
CPU)
>   Origin = "GenuineIntel"  Id = 0x106a5  Stepping = 5
>   
Features=0xbfebfbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CLFLUSH,DTS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE>
>   
Features2=0x9ce3bd<SSE3,DTES64,MON,DS_CPL,VMX,EST,TM2,SSSE3,CX16,xTPR,PDCM,DCA,SSE4.1,SSE4.2,POPCNT>
>   AMD Features=0x28100800<SYSCALL,NX,RDTSCP,LM>
>   AMD Features2=0x1<LAHF>
>   TSC: P-state invariant
> real memory  = 8589934592 (8192 MB)
> avail memory = 8247111680 (7865 MB)
> ACPI APIC Table: <DELL   PE_SC3  >
> FreeBSD/SMP: Multiprocessor System Detected: 4 CPUs
> FreeBSD/SMP: 1 package(s) x 2 core(s) x 2 SMT threads
>  cpu0 (BSP): APIC ID: 16
>  cpu1 (AP): APIC ID: 17
>  cpu2 (AP): APIC ID: 18
>  cpu3 (AP): APIC ID: 19
> ioapic1: Changing APIC ID to 1
> ioapic0 <Version 2.0> irqs 0-23 on motherboard
> ioapic1 <Version 2.0> irqs 32-55 on motherboard
> ...
> -----------------
> 
> We was expecting to see "1 package(s) x 4 core(s) x 2 SMT threads" and 8 
usable "cpus" 
> Instead. According to sysctl:
> 
> kern.smp.cpus: 4
> kern.smp.maxcpus: 32
> hw.ncpu: 4
> machdep.hlt_cpus: 0
> 
> We have made no change to the BIOS settings (all settings are set by default 
by Dell).
> Could anyone help us with an explanation for this issue?

Can you get the output of 'acpidump -t'?  Also, the 'x 2 cores x 2 SMT 
threads' bit is based on registers read from the CPU.  It is really claiming 
to be a 2x2 chip (2 cores with 2 threads each).  Maybe see what 
/usr/ports/misc/cpuid claims?

-- 
John Baldwin