3.7 /proc/<pid>/task/<tid>/children - Information about task children
3.8 /proc/<pid>/fdinfo/<fd> - Information about opened file
3.9 /proc/<pid>/map_files - Information about memory mapped files
+ 3.10 /proc/<pid>/timerslack_ns - Task timerslack value
4 Configuring procfs
4.1 Mount options
a7cb1000-a7cb2000 ---p 00000000 00:00 0
a7cb2000-a7eb2000 rw-p 00000000 00:00 0
a7eb2000-a7eb3000 ---p 00000000 00:00 0
-a7eb3000-a7ed5000 rw-p 00000000 00:00 0 [stack:1001]
+a7eb3000-a7ed5000 rw-p 00000000 00:00 0
a7ed5000-a8008000 r-xp 00000000 03:00 4222 /lib/libc.so.6
a8008000-a800a000 r--p 00133000 03:00 4222 /lib/libc.so.6
a800a000-a800b000 rw-p 00135000 03:00 4222 /lib/libc.so.6
[heap] = the heap of the program
[stack] = the stack of the main process
- [stack:1001] = the stack of the thread with tid 1001
[vdso] = the "virtual dynamic shared object",
the kernel system call handler
[anon:<name>] = an anonymous mapping that has been
The /proc/PID/task/TID/maps is a view of the virtual memory from the viewpoint
of the individual tasks of a process. In this file you will see a mapping marked
-as [stack] if that task sees it as a stack. This is a key difference from the
-content of /proc/PID/maps, where you will see all mappings that are being used
-as stack by all of those tasks. Hence, for the example above, the task-level
-map, i.e. /proc/PID/task/TID/maps for thread 1001 will look like this:
+as [stack] if that task sees it as a stack. Hence, for the example above, the
+task-level map, i.e. /proc/PID/task/TID/maps for thread 1001 will look like this:
08048000-08049000 r-xp 00000000 03:00 8312 /opt/test
08049000-0804a000 rw-p 00001000 03:00 8312 /opt/test
comparing their inode numbers to figure out which anonymous memory areas
are actually shared.
+3.10 /proc/<pid>/timerslack_ns - Task timerslack value
+---------------------------------------------------------
+This file provides the value of the task's timerslack value in nanoseconds.
+This value specifies a amount of time that normal timers may be deferred
+in order to coalesce timers and avoid unnecessary wakeups.
+
+This allows a task's interactivity vs power consumption trade off to be
+adjusted.
+
+Writing 0 to the file will set the tasks timerslack to the default value.
+
+Valid values are from 0 - ULLONG_MAX
+
+An application setting the value must have PTRACE_MODE_ATTACH_FSCREDS level
+permissions on the task specified to change its timerslack_ns value.
+
+
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Configuring procfs
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