The pmap command in Linux is used to display the memory map of a process. A memory map indicates how memory is spread out.
How do I run a pmap command?
Basic usage is simple. Just execute the ‘pmap’ command without any option. Of course, you need to pass a process PID as input. So there you go, the output first shows you the name of the process and then follows it up with the memory map.
What is anon in pmap?
Anonymous memory: Memory not relating to any named object or file within the file system is reported as [ anon ]. The pmap command displays common names for certain known anonymous memory mappings, such as: [ heap ] The process heap.
What is a process memory map?
File mapping or File-backed mapping − This mapping maps the area of the process’ virtual memory to the files. This means reading or writing to those areas of memory causes the file to be read or written. … When two processes map the same region of a file, they share the same pages of physical memory.
What is the use of top command in Linux?
top command in Linux with Examples. top command is used to show the Linux processes. It provides a dynamic real-time view of the running system. Usually, this command shows the summary information of the system and the list of processes or threads which are currently managed by the Linux Kernel.
What is RSS in memory?
In computing, resident set size (RSS) is the portion of memory occupied by a process that is held in main memory (RAM). The rest of the occupied memory exists in the swap space or file system, either because some parts of the occupied memory were paged out, or because some parts of the executable were never loaded.
What is anon memory?
Anonymous memory is a memory mapping with no file or device backing it. This is how programs allocate memory from the operating system for use by things like the stack and heap. Initially, an anonymous mapping only allocates virtual memory.
Is MMAP a system call?
In computing, mmap(2) is a POSIX-compliant Unix system call that maps files or devices into memory. It is a method of memory-mapped file I/O. It implements demand paging because file contents are not read from disk directly and initially do not use physical RAM at all.
What are the types of memory?
Most scientists believe there are at least four general types of memory:
- working memory.
- sensory memory.
- short-term memory.
- long-term memory.
What are types of cache memory?
There are three different categories, graded in levels: L1, L2 and L3. L1 cache is generally built into the processor chip and is the smallest in size, ranging from 8KB to 64KB. However, it’s also the fastest type of memory for the CPU to read.