Key Fields in /proc/cpuinfo

• physical id – unique identifier for each physical processor package (socket).
• cpu cores – number of physical cores inside one package.
• processor – logical CPU identifier; every SMT sibling is counted separately.

Definitions

Relationship:

logical_cpus = sockets × cores_per_socket × threads_per_core

If the result is larger than sockets × cores_per_socket, Hyper-Threading (or another SMT implementation) is active.

Quick Queries

# Number of sockets
awk '/physical id/ {print $4}' /proc/cpuinfo | sort -u | wc -l

# Cores per socket
awk '/cpu cores/ {print $4; exit}' /proc/cpuinfo

# Total logical CPUs
awk '/processor/ {++c} END {print c}' /proc/cpuinfo

# CPU model and count
grep -m1 'model name' /proc/cpuinfo | sed 's/.*: *//'

# Human-readable summary
lscpu

Example Output

$ lscpu
Architecture:        x86_64
CPU(s):              64
Thread(s) per core:  2
Core(s) per socket:  16
Socket(s):           2
Model name:          Intel(R) Xeon(R) Silver 4314 CPU @ 2.40GHz

Interpretation: two sockets, 16 cores each, 2 threads per core → 64 logical CPUs.

Per-Process Resource Usage

# Top 10 CPU consumers
ps -eo pid,ppid,cmd,%cpu --sort=-%cpu | head

# Top 10 memory consumers
ps -eo pid,ppid,cmd,%mem --sort=-%mem | head

# Top 10 virtual-memory consumers
ps -eo pid,ppid,cmd,vsz --sort=-vsz | head

Field reference:

• %CPU – percentage of CPU time used since last update.
• %MEM – resident set size as a percentage of total RAM.
• VSZ – virtual memory size in KiB.
• STAT – process state (R running, S sleeping, D uninterruptible, Z zombie, etc.).

Sample Session

$ awk '/physical id/ {print $4}' /proc/cpuinfo | sort -u | wc -l
2

$ awk '/cpu cores/ {print $4; exit}' /proc/cpuinfo
6

$ awk '/processor/ {++c} END {print c}' /proc/cpuinfo
24

$ grep -m1 'model name' /proc/cpuinfo
model name  : Intel(R) Xeon(R) CPU E5-2630 0 @ 2.30GHz

Result: 2 sockets, 6 cores per socket, Hyper-Threading enabled → 24 logical CPUs.