I've been monitoring my Centos with vmstat 1 $ cat /etc/centos-release CentOS Linux release 7.3.1611 (Core) Here is the output: enter image description here So why swpd is above 0 but si & so = 0 all the time Could someone please explain it?


The swpd column shows the amount of swap in use, the si and so columns show the swap activity in the time period represented by each line. In your example, you’re using 39,868 KiB of swap, but nothing is causing any swap activity so si and so are zero.

| improve this answer | |
  • Hi Stephen Kitt. Thanks for replying. But for me this situation is not clear because there is a planty amount of free RAM. – Kiyv_Ukraine Jan 18 '18 at 8:13
  • 1
    That’s fine, the fact that there is lots of free memory doesn’t mean swap won’t be used (for pages which are never used at all and therefore don’t need to be in physical memory). This question provides some background. – Stephen Kitt Jan 18 '18 at 8:17

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.