Memory and CPU, both are crucial part of ESXi, sometimes admins over-commit memory of ESXi unintentionally. ESXi has defined threshold to manage memory pressure and uses below memory reclamation techniques.
Now, Q :- When will ESXi start memory reclamation techniques ? - Transparent Page sharing
- Ballooning
- Memory compression
- Swapping
Ans: ESXi uses some memory states "High, Clear, Soft, Hard & Low" prior stating memory reclamation.
You can find lot of blogs to know more about above information so, I am not going to cover, what is TPS, ballooning etc. I am writing this blog to share the information, how to check what states and how many times ESXi went for.
memstats is the command used to check memory states.
By default, it shows much more information but use -s option and specify desired columns.
It's a great tool to get better understanding to check whether host is under memory pressure or not.
