sar command

$> sar -V
sysstat version 12.7.4
(C) Sebastien Godard (sysstat <at> orange.fr)

# CPU 코어 0을 1초 단위로 1번 수집하기
$> sar -P 0 1 1
Linux 6.5.5-1-MANJARO (geeksaga)  11/02/2023      _x86_64_        (16 CPU)

03:49:45 PM     CPU     %user     %nice   %system   %iowait    %steal     %idle
03:49:46 PM       0      3.06      0.00      1.02      0.00      0.00     95.92
Average:          0      3.06      0.00      1.02      0.00      0.00     95.92

# 모든 CPU를 2초 단위로 3번 수집하기
$> sar -u 2 3
Linux 6.5.5-1-MANJARO (geeksaga)  11/02/2023      _x86_64_        (16 CPU)

03:53:50 PM     CPU     %user     %nice   %system   %iowait    %steal     %idle
03:53:52 PM     all      1.63      0.00      1.79      0.06      0.00     96.52
03:53:54 PM     all      3.75      0.06      3.63      0.19      0.00     92.37
03:53:56 PM     all      2.36      0.03      1.73      0.06      0.00     95.81
Average:        all      2.58      0.03      2.38      0.11      0.00     94.91

$> sar --help
Usage: sar [ options ] [ <interval> [ <count> ] ]
Main options and reports (report name between square brackets):
        -B      Paging statistics [A_PAGE]
        -b      I/O and transfer rate statistics [A_IO]
        -d      Block devices statistics [A_DISK]
        -F [ MOUNT ]
                Filesystems statistics [A_FS]
        -H      Hugepages utilization statistics [A_HUGE]
        -I [ SUM | ALL ]
                Interrupts statistics [A_IRQ]
        -m { <keyword> [,...] | ALL }
                Power management statistics [A_PWR_...]
                Keywords are:
                BAT     Batteries capacity
                CPU     CPU instantaneous clock frequency
                FAN     Fans speed
                FREQ    CPU average clock frequency
                IN      Voltage inputs
                TEMP    Devices temperature
                USB     USB devices plugged into the system
        -n { <keyword> [,...] | ALL }
                Network statistics [A_NET_...]
                Keywords are:
                DEV     Network interfaces
                EDEV    Network interfaces (errors)
                NFS     NFS client
                NFSD    NFS server
                SOCK    Sockets (v4)
                IP      IP traffic      (v4)
                EIP     IP traffic      (v4) (errors)
                ICMP    ICMP traffic    (v4)
                EICMP   ICMP traffic    (v4) (errors)
                TCP     TCP traffic     (v4)
                ETCP    TCP traffic     (v4) (errors)
                UDP     UDP traffic     (v4)
                SOCK6   Sockets (v6)
                IP6     IP traffic      (v6)
                EIP6    IP traffic      (v6) (errors)
                ICMP6   ICMP traffic    (v6)
                EICMP6  ICMP traffic    (v6) (errors)
                UDP6    UDP traffic     (v6)
                FC      Fibre channel HBAs
                SOFT    Software-based network processing
        -q [ <keyword> [,...] | PSI | ALL ]
                System load and pressure-stall statistics
                Keywords are:
                LOAD    Queue length and load average statistics [A_QUEUE]
                CPU     Pressure-stall CPU statistics [A_PSI_CPU]
                IO      Pressure-stall I/O statistics [A_PSI_IO]
                MEM     Pressure-stall memory statistics [A_PSI_MEM]
        -r [ ALL ]
                Memory utilization statistics [A_MEMORY]
        -S      Swap space utilization statistics [A_MEMORY]
        -u [ ALL ]
                CPU utilization statistics [A_CPU]
        -v      Kernel tables statistics [A_KTABLES]
        -W      Swapping statistics [A_SWAP]
        -w      Task creation and system switching statistics [A_PCSW]
        -y      TTY devices statistics [A_SERIAL]

$> tldr sar

  sar

  Monitor performance of various Linux subsystems.
  More information: https://manned.org/sar.

  - Report I/O and transfer rate issued to physical devices, one per second (press CTRL+C to quit):
    sar -b 1

  - Report a total of 10 network device statistics, one per 2 seconds:
    sar -n DEV 2 10

  - Report CPU utilization, one per 2 seconds:
    sar -u ALL 2

  - Report a total of 20 memory utilization statistics, one per second:
    sar -r ALL 1 20

  - Report the run queue length and load averages, one per second:
    sar -q 1

  - Report paging statistics, one per 5 seconds:
    sar -B 5