Common output options of the System Observation command sar

Sar is a very useful system observation command in linux. It can observe disk io, cpu, block device, memory, swap, and other information to help us review the operating system status. The following lists some common system status display commands.

Sar-B: disk IO transmission statistics
Five values are displayed by default:

Tps: the total number of io requests sent to physical devices per second. The value is equal to rtps + wtpsrtps: Total number of read io requests per second wtps: Total number of write io requests per second bread/s: total number of read blocks per second bwrtn/s: Total number of write blocks per second

Sar-C: System Call (cpu)
Six values are displayed by default:

User: cpu usage of user space nice: Percentage of cpu time in user mode with NICE value. System: Percentage of cpu time occupied by system space iowait: Percentage of cpu time occupied by waiting for io requests steal: the percentage of cpu time that the hypervisor waits for to provide services for another virtual process. Idle: Percentage of idle cpu

Sar-d: displays information about each device in the active status.
8 values are displayed by default:

Tps: Total number of io messages sent to physical devices per second (rd_sec/s): number of Read Device sectors per second (one sector is 512 bytes) wr_sec/s: number of sectors written to the device per second avgrq-sz: Average number of sectors sent to the device per second avgqu-sz: average queue length sent to the device per second await: average I/O Request svctm sent to the device service: Average service time sent to the device request util: cpu time percentage of the I/O Request

Sar-I {int [,...] | SUM | ALL | XALL}: Statistical data of a given interrupt report
Two values are displayed by default:

INTR: indicates the number of interrupted devices. intr/s indicates the number of interrupted devices per second.

Sar-m: cpu power frequency statistics
Two values are displayed by default:

CPU: cpu information MHZ: cpu clock frequency

Sar-n {keyword [,...] | ALL}: Provides the network statistics report.
This command displays a lot of information. You can view the details by yourself.

Sar-P {cpu [,...] | ALL}: displays the cpu status information.

Sar-P n 1: displays the details of the n-th cpu. sar-p all 1: displays the details of ALL CPUs.

Sar-q: Display queue length and average load
By default, there are 5 values:

Runq-sz: queue length of a running process (this value is too high, indicating that many processes are queuing) plist-sz: Total ldavg-1 in the Process List: average load ldavg-5 for the past 1 minute: average load ldavg-15 for the past 5 minutes: average load for the past 15 minutes

Sar-r: displays seven default values for memory utilization:

Kbmemfree: Number of idle available memory (in bytes) kbmemused: The amount of memory used, but does not consider the memory usage of the kernel itself: average percentage of memory used kbbuffers: used for the total memory in the buffer kbcached: Used for the total memory in the cache kbcommit: The amount of memory required by the current workload, which is an estimated number commit: percentage of memory required for the current workload and total memory (RAM + swap partition ).

Sar-R: displays the memory status.
By default, there are three values:

Frmpg/s: Number of memory pages released per second by the system. A negative value indicates the number of pages allocated by the system, negative value indicates that a small number of pages are used for buffercampg/s: the number of additional memory pages used by the operating system for cache per second. negative value indicates that a small number of pages are used for cache

Sar-u [ALL]: displays cpu utilization
By default, there are many values. Most of the parameters are the same as-C. Here, if-C does not exist, ALL displays ALL cpu

System: the percentage of cpu used by the system space, including the time for soft and hard interrupt services. sys: the percentage of cpu used by the system space, no time for soft Interrupt or hard interrupt service irq: Percentage of cpu consumed by hard interrupt soft: Percentage of cpu consumed by soft Interrupt guest: percentage of cpu time used to run a virtual processor

Sar-v: displays the inode status.
The default value is 4:

Dentunusd: Number of cache entries not used in directory cache file-nr: number of file handles used by the system inode-nr: Number of inode handles used by the system pty-nr: operating System Pseudo Terminal usage

Sar-w: Process Creation and system switching
The default value is 2:

Proc/s: Number of processes created per second cswch/s: Number of context switches per second

Sar-W: swap partition information
The default value is 2:

Pswpin/s: Total number of pages written to the swap partition per second pswpout/s: Total number of pages written to the disk from the swap partition page per second