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https://chrisdown.name/2018/01/02/in-defence-of-swap.html This post is also available in Japanese , Chinese , and Russian . tl;dr: Having swap is a reasonably important part of a well functioning system. Without it, sane memory management becomes harder to achieve. Swap is not generally about getting emergency memory, it's about making memory reclamation egalitarian and efficient. In fact, using it as "emergency memory" is generally actively harmful. Disabling swap does not prevent disk I/O from becoming a problem under memory contention, it simply shifts the disk I/O thrashing from anonymous pages to file pages. Not only may this be less efficient, as we have a smaller pool of pages to select from for reclaim, but it may also contribute to getting into this high contention state in the first place. The swapper on kernels before 4.0 has a lot of pitfalls, and has contributed to a lot of people's negative perceptions about swap due to its overeagerness to swap out

Environment Red Hat Enterprise Linux 4, 5, 6, 7, 8 Issue How do I blacklist a kernel module to prevent it from loading automatically? How to disable a kernel module? How to disable a specific device driver? Resolution In order to prevent kernel modules loading during boot, the module name must be added into the blacklist file. Ensure the module is not configured to load either in /etc/modprobe.conf , /etc/modprobe.d/* , /etc/rc.modules , or /etc/sysconfig/modules/* before making the following modifications. Due to differences between the various versions of RHEL, please be sure to follow the appropriate steps for your system's version below: The shared steps for RHEL 5, 6, 7, 8 followed by the specific steps for each version The steps for RHEL 4 Shared Initial Steps for Red Hat Enterprise Linux 5, 6, 7 and 8 Kernel modules can be loaded directly, loaded as a dependency from another module, or during the boot