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What does VmRSS mean?
VmRSS is the measure of how much RAM the process is actually using. VmSize includes RSS, plus things like shared libraries and memory mapped files (which don’t actually use RAM), as well as allocated, but unused, memory.
What is proc PID FD?
These are links that point to the open files of the process whose pid is $PID. Fd stands for “file descriptors”, which is an integer that identifies any program input or output in UNIX-like systems. >
What is proc PID CWD?
/proc/PID/cwd, a symlink to the current working directory of the process. /proc/PID/environ contains the names and values of the environment variables that affect the process. /proc/PID/fd, a directory containing a symbolic link for each open file descriptor.
What is proc stat?
/proc/stat file. All of the numbers reported in this file are aggregates since the system first booted. These numbers identify the amount of time the CPU has spent performing different kinds of work. Time units are in USER_HZ or Jiffies (typically hundredths of a second).
What is VmPeak?
VmPeak is the maximum amount of memory the process has used since it was started. In order to track the memory usage of a process over time, you can use a tool called munin to track, and show you a nice graph of the memory usage over time.
What is ETC proc?
/proc is very special in that it is also a virtual filesystem. It’s sometimes referred to as a process information pseudo-file system. It doesn’t contain ‘real’ files but runtime system information (e.g. system memory, devices mounted, hardware configuration, etc).
What is the meaning of values at proc / [ PID / Stat?
Obsolete, because it does not provide information on real-time signals; use /proc/ [pid]/status instead. (35) wchan %lu [PT] This is the “channel” in which the process is wait‐ ing. It is the address of a location in the kernel where the process is sleeping.
What happens when VSS and vmrss are equal?
If they are close to equal, that means your process is sitting comfortably in memory. If VSS is much larger, that means there isn’t enough memory and parts of it have to be swapped out to disk (i.e., because of a competing process, etc.). * VmPeak: Peak virtual memory size.
How to calculate vmrss and resident set size?
You can get Page Size with getconf PAGESIZE command or in C/C++ program by calling sysconf (_SC_PAGE_SIZE) (defined in unistd.h). This will give you page size in bytes. Divide it with 1024 to get page size in KB. Thus, resident set size in KB is 46703 x 4 = 186812 kB (VmRSS).
How does VSS and resident set size match?
If VSS is much larger, that means there isn’t enough memory and parts of it have to be swapped out to disk (i.e., because of a competing process, etc.). * VmPeak: Peak virtual memory size. * VmSize: Virtual memory size.