Vmstat
From Dikapedia
Add notes: https://www.linode.com/docs/guides/use-vmstat-to-monitor-system-performance/
Add, by default it shows in Kilobytes!!!
vmstat - Report virtual memory statistics.
$ vmstat procs -----------memory---------- ---swap-- -----io---- -system-- ------cpu----- r b swpd free buff cache si so bi bo in cs us sy id wa st 0 0 0 272904 0 235736 0 0 1 3 12 22 0 0 100 0 0
$ vmstat 1 5 procs -----------memory---------- ---swap-- -----io---- -system-- ------cpu----- r b swpd free buff cache si so bi bo in cs us sy id wa st 0 0 0 388256 2088 319304 0 0 9550 34 192 220 4 0 87 8 0 0 0 0 388248 2088 319304 0 0 0 0 55 120 0 0 100 0 0 0 0 0 388248 2088 319304 0 0 0 0 62 128 0 0 100 0 0 0 0 0 388248 2088 319304 0 0 0 0 70 135 0 0 100 0 0 0 0 0 388248 2088 319304 0 0 0 0 68 128 0 0 100 0 0
- Print 5 times, every 1 second
$ vmstat -S M procs -----------memory---------- ---swap-- -----io---- -system-- ------cpu----- r b swpd free buff cache si so bi bo in cs us sy id wa st 0 0 0 378 2 311 0 0 9475 34 191 219 4 0 87 8 0
- -S = requires k, K, m or M (default is KiB)
How to run vmstat continuously
This is good if you want to monitor free memory continuously.
$ vmstat -S M 2 -t procs -----------memory---------- ---swap-- -----io---- -system-- ------cpu----- -----timestamp----- r b swpd free buff cache si so bi bo in cs us sy id wa st UTC 0 0 0 542 1 317 0 0 842 5892 649 1104 18 5 69 3 5 2023-08-28 16:30:04 0 0 0 542 1 317 0 0 0 0 30 49 0 0 100 0 0 2023-08-28 16:30:06 0 0 0 542 1 317 0 0 0 0 27 48 0 0 100 0 0 2023-08-28 16:30:08 0 0 0 542 1 317 0 0 0 0 27 47 0 0 100 0 0 2023-08-28 16:30:10 0 0 0 542 1 317 0 0 0 0 27 48 0 0 100 0 0 2023-08-28 16:30:12 0 0 0 542 1 317 0 0 0 6 32 52 0 0 100 0 0 2023-08-28 16:30:14
- -S = Size is in MB
- 2 = print every 2 sec
- -t = include timestamp
References: [+] https://www.cyberciti.biz/faq/linux-check-memory-usage/