]/cgroup (since Linux 2.6.24) This file describes control groups to which the process/task belongs. For each cgroup hierarchy there is one entry contain‐ ing colon-separated fields of the form: 5:cpuacct,cpu,cpuset:/daemons The colon-separated fields are, from left to right: 1. hierarchy ID number 2. set of subsystems bound to the hierarchy 3. control group in the hierarchy to which the process belongs This file is present only if the CONFIG_CGROUPS kernel configu‐ ration option is enabled. _Referenced and ACCESSED/YOUNG bits and, after some measured time interval, once again inspects the values in the "Refer‐ enced:" fields to get an idea of the change in memory footprint of the process during the measured interval. If one is inter‐ ested only in inspecting the selected mapping types, then the value 2 or 3 can be used instead of 1. A further value can be written to affect a different bit:. Writing any value to /proc/[pid]/clear_refs other than those listed above has no effect. The /proc/[pid]/clear_refs file is present only if the CON‐ FIG_PROC_PAGE_MONITOR kernel configuration option is enabled. /proc/[pid]/cmdline This holds the complete command line for the process, unless the process is a zombie. In the latter case, there is nothing in this file: that is, a read on this file will return 0 charac‐ ters. The command-line arguments appear in this file as a set of strings separated by null bytes ('\0'), with a further null byte: $ strings /proc/1/environ /proc/[pid]/exe Under Linux 2.2 and later, this file is a symbolic link contain‐ ing the actual pathname of the executed command. This symbolic link can be dereferenced normally; attempting to open it will open the executable. You can even type /proc/[pid]/exe to run another copy of the same executable as is being run by process [pid]. In a multithreaded process, the contents of this sym‐ bolic link are not available if the main thread has already ter‐ minated (typically by calling pthread_exit(3)). epoll_create(2), eventfd(2), ino‐ tify_init(2), signalfd(2), and timerfd(2)), the entry will be a symbolic link with contents of the form anon_inode:<file-type> In some cases,‐ set. mea‐ surement for each of the process's resource limits (see getr‐ limit(2)). Up to and including Linux 2.6.35, this file is pro‐‐. /proc/[pid]/maps A file containing the currently mapped memory regions and their access permissions. See mmap(2) for some further information about memory mappings.‐. [heap] The process's heap. If the pathname field is blank, this is an anonymous mapping as obtained via the mmap(2) function.)). (2) parent ID: ID of parent mount (or of self for the top of the mount tree). (3) major:minor: value of st_dev for files on filesystem (see stat(2)).  in the form "type[.sub‐ type]". (10) mount source: filesystem-specific information or "none". (11) super options: per-superblock options. Parsers should ignore all unrecognized optional fields. filesystems currently mounted in the process's mount namespace. The format of this file is docu‐ mented. /proc/[pid]/mountstats (since Linux 2.6.17) This file exports information (statistics, configuration infor‐‐ rently (as at Linux 2.6.26), only NFS filesystems export information via this field. This file is readable only by the owner of the process. /proc/[pid] ter‐ minate. names‐ pace ter‐ minate.).  Swap: 0 kB KernelPageSize: 4 kB MMUPageSize: 4 kB Locked: 0 kB The first of these lines shows the same information as is dis‐‐: rd - readable wr - writ - mergable advise flag The /proc/[pid]/smaps file is present only if the CON) calculations. stime %lu (15) Amount of time that this process has been scheduled in kernel mode, measured in clock ticks (divide by sysconf(_SC_CLK_TCK)). cutime %ld (16) Amount of time that this process's waited-for children have been scheduled in user mode, measured in clock ticks (divide by sysconf(_SC_CLK_TCK)). (See also times(2).) This includes guest time, cguest_time (time spent running a virtual CPU, see below). cstime %ld ) The time in jiffies before the next SIGALRM is sent to the process due to an interval timer. Since kernel 2.6.17, this field is no longer maintained, and is hard coded as 0. starttime %llu (was %lu before Linux 2.6) ) This is the "channel" in which the process is waiting. It is the address of a location in the kernel where the process is sleeping. The corre‐ sponding symbolic name can be found in /proc/[pid]/wchan. nswap %lu ) The fields are as follows: * Name: Command run by this process. * State: Current state of the process. One of "R (running)", "S (sleeping)", "D (disk sleep)", "T (stopped)", "T (tracing stop)", "Z (zombie)", or "X (dead)". * Tgid: Thread group ID (i.e., Process ID). *. * VmPeak: Peak virtual memory size. * VmSize: Virtual memory size. * VmLck: Locked memory size (see mlock(3)). *‐_context_switches, nonvoluntary_context_switches: Number of voluntary and involuntary context switches (since Linux 2.6.23). ‐ tories. For attributes that are shared by all threads, the con‐‐ with the string "ID:". For example:.sival_ptr value supplied to the signal han‐ dler.‐‐ tem is specified and it didn't manage to determine the filesys‐ tem type. Then filesystems‐‐‐‐ rated by a slash (/). The first of these is the number of cur‐‐ fileds are displayed only if the kernel was config‐ ured with various options; those dependencies are noted in the list. MemTotal %lu Total usable RAM (i.e., physical RAM minus a few reserved bits and the kernel binary code). MemFree %lu The sum of LowFree+HighFree.‐ mmaped, such as libraries. Shmem %lu (since Linux 2.6.32) [To be documented.] Slab %lu In-kernel data structures cache. SReclaimable %lu (since Linux 2.6.19) Part of Slab, that might be reclaimed, such as caches. SUnreclaim %lu (since Linux 2.6.19) Part of Slab, that cannot be reclaimed on memory pres‐) = ([total RAM pages] - [total huge TLB pages]) * overcommit_ratio / 100 + [total swap pages] mit_hugepages. Hugepagesize %lu (CONFIG_HUGETLB_PAGE is required.) The size of huge pages. /proc/modules A text list of the modules that have been loaded by the system. See also lsmod(8). /proc/mounts Before kernel 2.4.19, this file was a list of all the filesys‐‐ mented in fstab(5). /proc/mtrr Memory Type Range Registers. See the Linux kernel source file Documentation/mtrr.txt for details. /proc/net various net pseudo-files, all of which give the status of some part of the networking layer. These files contain ASCII struc‐‐‐ ator of the socket. /proc/net/udp Holds a dump of the UDP data‐. Since Linux 2.6.16 this file is present only if the CONFIG_SLAB kernel configuration option is enabled. The columns in /proc/slabinfo are:. /proc/sys/abi (since Linux 2.4.10) This directory may contain files with application binary infor‐ mation. See the Linux kernel source file Documenta‐ increas‐ ing this value: echo 100000 > /proc/sys/fs/file-max The kernel constant NR_OPEN imposes an upper limit on the value that may be placed in‐ behav‐ iour creden‐ tials filesystem UID of the process following the link matches the owner (UID) of the symbolic link (as described in creden‐ determines whether core dump files are produced for set-user-ID or otherwise protected/tainted bina‐ ries. Three different integer values can be specified: 0 (default) This provides the traditional (pre-Linux 2.6.13) behav‐ filesystem‐ tern must either be an absolute pathname or a pipe com‐ mand, as detailed in core(5). Warnings will be written to the kernel log if core_pattern does not follow these rules, and no core dump will be produced. ‐ quency. If BSD-style process accounting is enabled, these val‐‐‐‐‐ tents. A value of 0 in this file imposes no restrictions. If the value is 1, only privileged users can read the kernel sys‐‐ (PowerPC only) If this file is set to a nonzero value, the Pow‐ erPC htab (see kernel file Documentation/powerpc/ppc_htab.txt) is pruned each time the system hits the idle loop. ‐ FIG_MODULES option enabled. /proc/sys/kernel/msgmax (since Linux 2.2). ‐_mes‐ sage_loglevel, minimum_console_level, and default_con‐ sole‐ sole_loglevel. ‐ rently in use. /proc/sys/kernel/random This directory contains various parameters controlling the oper‐ ation of the file /dev/random. See random(4) for further infor‐‐ tation/sched_rr_timeslice_ms (since Linux 3.9) See sched_rr_get_interval(2). ‐‐‐ figuration option is enabled. For further details see the Linux kernel/vm This directory contains files for memory management tuning, buf‐ fer and cache management. /proc/sys/vm/drop_caches (since Linux 2.6.16) Writing to this file causes the kernel to drop clean caches, dentries, and inodes from memory, causing that memory to become free. This can be useful for memory management testing and per‐(8)‐ able page mapped as soon as the corruption is detected. Note this is not supported for a few types of pages, like kernel internally allocated data or the swap cache, but works for the majority of user pages. 0: Only unmap the corrupted page from all processes and kill only a process that tries to access it.. Only present if the kernel was configured with CONFIG_MEM‐ ting‐rq-trigger (since Linux 2.4.21) Writing a character to this file triggers the same SysRq func‐ tion as typing ALT-SysRq-<character> (see the description of /proc/sys/kernel/sysrq). This file is normally writable only by root. For further details see the Linux kernel source file Doc‐ umentation/sysrq.txt.   Docu‐ mentation/sysctl/fs.txt, Documentation/sysctl/kernel.txt, Documenta‐ tion/sysctl/net.txt, and Documentation/sysctl/vm.txt. COLOPHON This page is part of release 3.65 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at. Linux 2014-04-12 PROC(5)[top]