Hardware correlation

Jordan_Hargrave at Dell.com Jordan_Hargrave at Dell.com
Fri Jun 23 13:11:25 CDT 2006


  There is only one entry per physical socket in the SMBIOS table.  This doesn't change if the CPU is HT/Dual core/etc.  On a two socket system, there will only be two entries in the SMBIOS Table, while there could be: 2 (single core, no HT), 4 (dual core/no HT, single core, HT) 8 (dual core+HT) entries in /procfs depending on the processor type and configuration.

--jordan hargrave
Dell Enterprise Linux Engineering

-----Original Message-----
From: Bart C. Wise [mailto:bwise at novell.com]
Sent: Fri 6/23/2006 12:23 PM
To: Hargrave, Jordan
Cc: libsmbios-devel at lists.us.dell.com
Subject: Re: Hardware correlation

Thanks for your information.

It was useful in seeing how SMBIOS enumerates the processors. I do have a 
question regarding the entries in the table. I have a single-processor system 
with HT enabled. However, SMBIOS is only showing a single CPU (procfs shows 
two processors with 2 siblings). Using your table below, it looks like I 
should get an entry for each thread in a HT'd CPU.  Does each hyperthreaded 
CPU have one or two entries in the SMBIOS table.? And does that change when 
the user enables/disables hyperthreading in the BIOS?

On Friday 23 June 2006 10:43, Jordan_Hargrave at dell.com wrote:
> SMBIOS only lists physical CPU slots, it doesn't list logical (HT) or dual
> core CPU IDs.
> On a 2-slot dual core system, with HT enabled (total 8 CPUs) the CPUs
> should be enumerated: 
> cpu0: Slot 0 : Core 0 : HT 0 
> cpu1: Slot 1 : Core 0 : HT 0
> cpu2: Slot 0 : Core 1 : HT 0
> cpu3: Slot 1 : Core 1 : HT 0
> cpu4: Slot 0 : Core 0 : HT 1
> cpu5: Slot 1 : Core 0 : HT 1
> cpu6: Slot 0 : Core 1 : HT 1
> cpu7: Slot 1 : Core 1 : HT 1
> The SLOT corresponds to the SMBIOS CPU.  If HT is disabled, or this is a
> single core system, the enumeration will be different. An easier way to
> calculate this is the SMBIOS CPU number should be the CPU number modulo the
> # of physical sockets.
> --jordan hargrave
> Dell Enterprise Linux Engineering
> -----Original Message-----
> From: libsmbios-devel-bounces at lists.us.dell.com on behalf of Bart C. Wise
> Sent: Fri 6/23/2006 11:06 AM
> To: libsmbios-devel at lists.us.dell.com
> Subject: Hardware correlation
> Michael,
> Is there a way to correlate the hardware between SMBIOS and other sources
> of information (procfs, sysfs, ACPI, SMBIOS, IPMI, etc.) on a Linux
> platform. For example, if we are dealing with a 4-processor system, how do
> we know that procfs' processor #3 is the same as SMBIOS' processor #3, and
> is the same as ACPI's processor #3. I know that procfs and sysfs use the
> same data, so they correlate; however, what about SMBIOS?
> Bart
> _______________________________________________
> libsmbios-devel mailing list
> libsmbios-devel at lists.us.dell.com
> http://lists.us.dell.com/mailman/listinfo/libsmbios-devel

More information about the libsmbios-devel mailing list