Merge tag 'docs-4.5' of git://git.lwn.net/linux

[cascardo/linux.git] / Documentation / filesystems / proc.txt

diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt
index 5d4f28a..fde9fd0 100644 (file)
--- a/Documentation/filesystems/proc.txt
+++ b/Documentation/filesystems/proc.txt
@@ -169,6 +169,9 @@ read the file /proc/PID/status:
   VmLck:         0 kB
   VmHWM:       476 kB
   VmRSS:       476 kB
+  RssAnon:             352 kB
+  RssFile:             120 kB
+  RssShmem:              4 kB
   VmData:      156 kB
   VmStk:        88 kB
   VmExe:        68 kB
@@ -231,14 +234,20 @@ Table 1-2: Contents of the status files (as of 4.1)
  VmSize                      total program size
  VmLck                       locked memory size
  VmHWM                       peak resident set size ("high water mark")
- VmRSS                       size of memory portions
+ VmRSS                       size of memory portions. It contains the three
+                             following parts (VmRSS = RssAnon + RssFile + RssShmem)
+ RssAnon                     size of resident anonymous memory
+ RssFile                     size of resident file mappings
+ RssShmem                    size of resident shmem memory (includes SysV shm,
+                             mapping of tmpfs and shared anonymous mappings)
  VmData                      size of data, stack, and text segments
  VmStk                       size of data, stack, and text segments
  VmExe                       size of text segment
  VmLib                       size of shared library code
  VmPTE                       size of page table entries
  VmPMD                       size of second level page tables
- VmSwap                      size of swap usage (the number of referred swapents)
+ VmSwap                      amount of swap used by anonymous private data
+                             (shmem swap usage is not included)
  HugetlbPages                size of hugetlb memory portions
  Threads                     number of threads
  SigQ                        number of signals queued/max. number for queue
@@ -265,7 +274,8 @@ Table 1-3: Contents of the statm files (as of 2.6.8-rc3)
  Field    Content
  size     total program size (pages)           (same as VmSize in status)
  resident size of memory portions (pages)      (same as VmRSS in status)
- shared   number of pages that are shared      (i.e. backed by a file)
+ shared   number of pages that are shared      (i.e. backed by a file, same
+                                               as RssFile+RssShmem in status)
  trs      number of pages that are 'code'      (not including libs; broken,
                                                        includes data segment)
  lrs      number of pages of library           (always 0 on 2.6)
@@ -459,7 +469,10 @@ and a page is modified, the file page is replaced by a private anonymous copy.
 hugetlbfs page which is *not* counted in "RSS" or "PSS" field for historical
 reasons. And these are not included in {Shared,Private}_{Clean,Dirty} field.
 "Swap" shows how much would-be-anonymous memory is also used, but out on swap.
-"SwapPss" shows proportional swap share of this mapping.
+For shmem mappings, "Swap" includes also the size of the mapped (and not
+replaced by copy-on-write) part of the underlying shmem object out on swap.
+"SwapPss" shows proportional swap share of this mapping. Unlike "Swap", this
+does not take into account swapped out page of underlying shmem objects.
 "Locked" indicates whether the mapping is locked in memory or not.
 
 "VmFlags" field deserves a separate description. This member represents the kernel
@@ -842,6 +855,7 @@ Dirty:             968 kB
 Writeback:           0 kB
 AnonPages:      861800 kB
 Mapped:         280372 kB
+Shmem:             644 kB
 Slab:           284364 kB
 SReclaimable:   159856 kB
 SUnreclaim:     124508 kB
@@ -898,6 +912,7 @@ MemAvailable: An estimate of how much memory is available for starting new
    AnonPages: Non-file backed pages mapped into userspace page tables
 AnonHugePages: Non-file backed huge pages mapped into userspace page tables
       Mapped: files which have been mmaped, such as libraries
+       Shmem: Total memory used by shared memory (shmem) and tmpfs
         Slab: in-kernel data structures cache
 SReclaimable: Part of Slab, that might be reclaimed, such as caches
   SUnreclaim: Part of Slab, that cannot be reclaimed on memory pressure