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In linux Servers there is always difficulty in finding the server is multi-processor, multi-core or Hyperthreading is enabled or not.

Let’s check this, but first keep in mind the following points:

1) Physical ID = Number assigned to each Processor on MotherBoard

2) Sibling ID = Number of logical processor provided by each Physical Processor

3) Core ID = Number of core in the Physical Processor

Note: If core Id is equal to sibling ID it means there is no Hyperthreading

If sibling ID is double that of core ID it supports Hyperthreading

Command: cat /proc/cpuinfo

Case 1:

Single-processor, Single-core, HT

processor 0 1
physical id 0 0
siblings 2 2
core id 0 0
cpu cores 1 1

The cpu cores value is “1”, so this system uses single-core processors.
The cpu cores value does not match the siblings value, so this system has hyperthreading.
There is one physical id listed, so this is a single-processor, single-core system with hyperthreading.

Case 2:

Single-processor, Dual-core, non-HT

processor 0 1
physical id 0 0
siblings 2 2
core id 0 1
cpu cores 2 2

The cpu cores value is “2” so the system uses dual-core processors.
The cpu cores value matches the siblings value, so this system does not have hyperthreading.
There is one physical id listed, so this is a single-processor, dual-core system without hyperthreading.

Case 3:

Dual-processor, Dual-core, HT

processor 0 1 2 3 4 5 6 7
physical id 0 0 0 0 1 1 1 1
siblings 4 4 4 4 4 4 4 4
core id 0 0 1 1 0 0 1 1
cpu cores 2 2 2 2 2 2 2 2

The cpu cores value is “2” so this system uses dual-core processors.
The cpu cores value does not match the siblings value, so this system has hyperthreading.
There are two physical IDs listed, so this is a dual-processor, dual-core machine with hyperthreading

Case 4:

Dual-processor, Quad-core, non-HT

processor 0 1 2 3 4 5 6 7
physical id 0 1 0 1 0 1 0 1
siblings 4 4 4 4 4 4 4 4
core id 0 0 1 1 2 2 3 3
cpu cores 4 4 4 4 4 4 4 4

The cpu cores value is “4”, so the system uses quad-core processors.
The cpu cores value matches the siblings value, so this system does not have hyperthreading.
There are two physical IDs listed, so this is a dual-processor, quad-core system without hyperthreading

Case 5:

Dual-processor, Quad-core, HT

processor 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
physical id 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1
siblings 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8
core id 0 0 1 1 2 2 3 3 0 0 1 1 2 2 3 3
cpu cores 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4

The cpu cores value is “4”, so the system uses quad-core processors.
The cpu cores value does not match the siblings value, so this system has hyperthreading.
There are two physical IDs listed, so this is a dual-processor, quad-core system with hyperthreading.