Doubt about physcial processors and logical processors

umeshgupta1987 · 08-08-2011, 01:38 AM

Hi friends,

i have two sun os server

I wanna know that how many physcial processors and logical processors are there??

server1

Code:

bash # psrinfo
0       on-line   since 07/24/2011 08:02:41
1       on-line   since 07/24/2011 08:02:41
2       on-line   since 07/24/2011 08:02:41
3       on-line   since 07/24/2011 08:02:40
bash # psrinfo -p
4
bash # psrinfo -pv
The physical processor has 1 virtual processor (0)
  UltraSPARC-IIIi (portid 0 impl 0x16 ver 0x24 clock 1062 MHz)
The physical processor has 1 virtual processor (1)
  UltraSPARC-IIIi (portid 1 impl 0x16 ver 0x24 clock 1062 MHz)
The physical processor has 1 virtual processor (2)
  UltraSPARC-IIIi (portid 2 impl 0x16 ver 0x24 clock 1062 MHz)
The physical processor has 1 virtual processor (3)
  UltraSPARC-IIIi (portid 3 impl 0x16 ver 0x24 clock 1062 MHz)

Server -2

Code:

bash # psrinfo
0       on-line   since 07/23/2011 23:56:50
1       on-line   since 07/23/2011 23:56:54
2       on-line   since 07/23/2011 23:56:56
3       on-line   since 07/23/2011 23:56:58
4       on-line   since 07/23/2011 23:57:00
5       on-line   since 07/23/2011 23:57:02
6       on-line   since 07/23/2011 23:57:04
7       on-line   since 07/23/2011 23:57:06

bash # psrinfo -p
4
bash # psrinfo -pv
The physical processor has 2 virtual processors (0 1)
  x86 (chipid 0x0 AuthenticAMD family 15 model 65 step 3 clock 2793 MHz)
        Dual-Core AMD Opteron(tm) Processor 8220
The physical processor has 2 virtual processors (2 3)
  x86 (chipid 0x1 AuthenticAMD family 15 model 65 step 3 clock 2793 MHz)
        Dual-Core AMD Opteron(tm) Processor 8220
The physical processor has 2 virtual processors (4 5)
  x86 (chipid 0x2 AuthenticAMD family 15 model 65 step 3 clock 2793 MHz)
        Dual-Core AMD Opteron(tm) Processor 8220
The physical processor has 2 virtual processors (6 7)
  x86 (chipid 0x3 AuthenticAMD family 15 model 65 step 3 clock 2793 MHz)
        Dual-Core AMD Opteron(tm) Processor 8220

so at server 1 physcial processor are 4 and logical processor are 8.

and at server 2 physcial processor are 4 and logical processor are 12.

Please suggest me that is it right or wrong???
Regards

Umesh

sunnydrake · 08-08-2011, 03:02 AM

looks like to me 1st 4 cores and 2nd 8! 4 cpus and total! 8 cores

jlliagre · 08-08-2011, 03:12 AM

1st one has four single core CPUs and 2nd has four dual core CPUs.

umeshgupta1987 · 08-08-2011, 03:15 AM

so my assumtion is right...

jlliagre · 08-08-2011, 06:33 AM

Both of your assumptions are incorrect about the logical processors count:

Quote:

server 1 physical processor are 4 and logical processor are 8.

logical processors are 4.

Quote:

server 2 physical processor are 4 and logical processor are 12.

logical processors are 8.

A physical CPU is also a logical CPU, they do not add up.

SuganX · 08-10-2011, 03:17 PM

I just recently had a similar issue which I had to explain to a junior Solaris admin.

First check the CPU type. Do some googling to see how many cores are supported in this particular CPU type. Older CPU's had no cores per CPU "chip". Newer ones now have multiple cores per CPU "chip".

In the first example, there are 4 physical CPU chips installed as per "psrinfo -p". "UltraSPARC-IIIi" (RISC CHIP) has no cores just one CPU so the logical and physical numbers will be the same, nothing wrong with that.

In the second example there are are 4 physical CPU chips installed as per "psrinfo -p". "Dual-Core AMD Opteron(tm) Processor 8220" (x64/CISC CHIP) has 2 cores because of the "Dual-Core" description. Therefore there are 8 logical processors.

It gets better... as an added example, UltraSPARC-VII has 4 cores per CPU chip and execute two hardware threads simultaneously per core. So a 1 CPU chip UltraSPARC-VII system has 8 logical processors (4cores x 2 hardware threads x 1 CPU)