帮助文档 内存管理 1 man malloc http://man7.org/linux/man-pages/man3/malloc.3.html Thread safety (多个线程可以同时执行) arena 1 2 3 4 5 To scalably handle memory allocation in multithreaded applications, glibc creates additional memory allocation arenas if mutex contention is detected. Each arena is a large region of memory that is internally allocated by the system (using brk(2) or mmap(2)),