How does the Linux kernel handle memory allocation for high-demand applications?

The Linux kernel is renowned for its efficient memory management capabilities, which are crucial for running high-demand applications like databases and high-performance computing resources. Understanding how the kernel manages memory allocation, paging, and swapping can offer insights into performance optimization and system stability. How does the allocator decide when to use cached memory versus invoking the Out-of-Memory (OOM) killer, and what strategies exist to prevent application crashes during peak load periods? Exploring these mechanisms can provide valuable knowledge for developers and system administrators looking to optimize resource utilization in Linux environments.