we have learned that this alert is giving false value after confirming from oracle support. as per them, when running "free -m" command - "In Oracle Linux 7/8, the focus should be on the "available" column. The available column estimates how much memory is available for starting new applications without swapping. If, the system still has 28G available memory and you see 26G in "used" - that is because this is how Linux behaves. Linux treats the memory that can be made available upon request as "used"."