About linux Low-end memory a problem was found in the server program a few days ago. When a cache function is enabled for some files on a disk (save some common results directly to the disk to avoid repeated computation ), the LowFree memory in/proc/meminfo of the operating system quickly decreases, basically close to 0. However, the program runs normally, and because of the cache, the CPU usage and load are greatly reduced, and the effect is obvious. Www.2cto.com later I checked some linux documents about LowFree and LowTotal in/proc/meminfo, as follows: LowTotal: The total amount of non-highmem memory. lowFree: The amount of free memory of the low memory region. this is the memory the kernel can address directly. all kernel datastructures need to go into low memory means that the low-end memory is the memory that the kernel can directly address. In a 32-bit operating system, LowFree is the 1 GB memory used by the kernel. On 64-bit machines, LowTotal and LowFree are actually equal to MemTotal and MemFree. The problem I encountered was actually because the operating system buffered the files in the memory after the files on the disk were used as the cache. Therefore, LowFree memory is reduced. When memory is needed, the memory used as the file buffer can be released at any time. So there is no problem.