summaryrefslogtreecommitdiffstats
path: root/Documentation/filesystems/proc.txt
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/filesystems/proc.txt')
-rw-r--r--Documentation/filesystems/proc.txt25
1 files changed, 18 insertions, 7 deletions
diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt
index a6aca8740883..e73df2722ff3 100644
--- a/Documentation/filesystems/proc.txt
+++ b/Documentation/filesystems/proc.txt
@@ -136,6 +136,7 @@ Table 1-1: Process specific entries in /proc
statm Process memory status information
status Process status in human readable form
wchan If CONFIG_KALLSYMS is set, a pre-decoded wchan
+ pagemap Page table
stack Report full stack trace, enable via CONFIG_STACKTRACE
smaps a extension based on maps, showing the memory consumption of
each mapping
@@ -370,17 +371,24 @@ Shared_Dirty: 0 kB
Private_Clean: 0 kB
Private_Dirty: 0 kB
Referenced: 892 kB
+Anonymous: 0 kB
Swap: 0 kB
KernelPageSize: 4 kB
MMUPageSize: 4 kB
-The first of these lines shows the same information as is displayed for the
-mapping in /proc/PID/maps. The remaining lines show the size of the mapping,
-the amount of the mapping that is currently resident in RAM, the "proportional
-set size” (divide each shared page by the number of processes sharing it), the
-number of clean and dirty shared pages in the mapping, and the number of clean
-and dirty private pages in the mapping. The "Referenced" indicates the amount
-of memory currently marked as referenced or accessed.
+The first of these lines shows the same information as is displayed for the
+mapping in /proc/PID/maps. The remaining lines show the size of the mapping
+(size), the amount of the mapping that is currently resident in RAM (RSS), the
+process' proportional share of this mapping (PSS), the number of clean and
+dirty private pages in the mapping. Note that even a page which is part of a
+MAP_SHARED mapping, but has only a single pte mapped, i.e. is currently used
+by only one process, is accounted as private and not as shared. "Referenced"
+indicates the amount of memory currently marked as referenced or accessed.
+"Anonymous" shows the amount of memory that does not belong to any file. Even
+a mapping associated with a file may contain anonymous pages: when MAP_PRIVATE
+and a page is modified, the file page is replaced by a private anonymous copy.
+"Swap" shows how much would-be-anonymous memory is also used, but out on
+swap.
This file is only present if the CONFIG_MMU kernel configuration option is
enabled.
@@ -397,6 +405,9 @@ To clear the bits for the file mapped pages associated with the process
> echo 3 > /proc/PID/clear_refs
Any other value written to /proc/PID/clear_refs will have no effect.
+The /proc/pid/pagemap gives the PFN, which can be used to find the pageflags
+using /proc/kpageflags and number of times a page is mapped using
+/proc/kpagecount. For detailed explanation, see Documentation/vm/pagemap.txt.
1.2 Kernel data
---------------
OpenPOWER on IntegriCloud