Why is SWAP disabled on some servers?

Disabling SWAP on some servers is related to performance characteristics and application behavior, especially in high-load or specialized systems.

Reasons for disabling SWAP:

• Predictability of performance. When using SWAP, some memory can be offloaded to disk, which significantly slows down application performance. This is unacceptable for latency-sensitive systems.

• Avoiding excessive disk usage. Frequent swapping can lead to SSD wear and reduce overall disk subsystem performance.

• Use of specialized memory. In some cases, servers are equipped with large amounts of RAM, and swap is not needed.

• Memory usage control. Instead of swap, mechanisms like cgroups in Linux are often used to limit memory to prevent unpredictable behavior.

Thus, disabling SWAP helps ensure stable and fast application performance, especially in time-critical systems.