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Diffstat (limited to 'Documentation/filesystems/proc.txt')
| -rw-r--r-- | Documentation/filesystems/proc.txt | 125 |
1 files changed, 118 insertions, 7 deletions
diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt index 8756a07f4dc3..4a37e25e694c 100644 --- a/Documentation/filesystems/proc.txt +++ b/Documentation/filesystems/proc.txt @@ -42,6 +42,7 @@ Table of Contents 2.12 /proc/<pid>/oom_adj - Adjust the oom-killer score 2.13 /proc/<pid>/oom_score - Display current oom-killer score 2.14 /proc/<pid>/io - Display the IO accounting fields + 2.15 /proc/<pid>/coredump_filter - Core dump filtering settings ------------------------------------------------------------------------------ Preface @@ -171,7 +172,9 @@ read the file /proc/PID/status: This shows you nearly the same information you would get if you viewed it with the ps command. In fact, ps uses the proc file system to obtain its information. The statm file contains more detailed information about the -process memory usage. Its seven fields are explained in Table 1-2. +process memory usage. Its seven fields are explained in Table 1-2. The stat +file contains details information about the process itself. Its fields are +explained in Table 1-3. Table 1-2: Contents of the statm files (as of 2.6.8-rc3) @@ -188,16 +191,65 @@ Table 1-2: Contents of the statm files (as of 2.6.8-rc3) dt number of dirty pages (always 0 on 2.6) .............................................................................. + +Table 1-3: Contents of the stat files (as of 2.6.22-rc3) +.............................................................................. + Field Content + pid process id + tcomm filename of the executable + state state (R is running, S is sleeping, D is sleeping in an + uninterruptible wait, Z is zombie, T is traced or stopped) + ppid process id of the parent process + pgrp pgrp of the process + sid session id + tty_nr tty the process uses + tty_pgrp pgrp of the tty + flags task flags + min_flt number of minor faults + cmin_flt number of minor faults with child's + maj_flt number of major faults + cmaj_flt number of major faults with child's + utime user mode jiffies + stime kernel mode jiffies + cutime user mode jiffies with child's + cstime kernel mode jiffies with child's + priority priority level + nice nice level + num_threads number of threads + start_time time the process started after system boot + vsize virtual memory size + rss resident set memory size + rsslim current limit in bytes on the rss + start_code address above which program text can run + end_code address below which program text can run + start_stack address of the start of the stack + esp current value of ESP + eip current value of EIP + pending bitmap of pending signals (obsolete) + blocked bitmap of blocked signals (obsolete) + sigign bitmap of ignored signals (obsolete) + sigcatch bitmap of catched signals (obsolete) + wchan address where process went to sleep + 0 (place holder) + 0 (place holder) + exit_signal signal to send to parent thread on exit + task_cpu which CPU the task is scheduled on + rt_priority realtime priority + policy scheduling policy (man sched_setscheduler) + blkio_ticks time spent waiting for block IO +.............................................................................. + + 1.2 Kernel data --------------- Similar to the process entries, the kernel data files give information about the running kernel. The files used to obtain this information are contained in -/proc and are listed in Table 1-3. Not all of these will be present in your +/proc and are listed in Table 1-4. Not all of these will be present in your system. It depends on the kernel configuration and the loaded modules, which files are there, and which are missing. -Table 1-3: Kernel info in /proc +Table 1-4: Kernel info in /proc .............................................................................. File Content apm Advanced power management info @@ -473,10 +525,10 @@ IDE devices: More detailed information can be found in the controller specific subdirectories. These are named ide0, ide1 and so on. Each of these -directories contains the files shown in table 1-4. +directories contains the files shown in table 1-5. -Table 1-4: IDE controller info in /proc/ide/ide? +Table 1-5: IDE controller info in /proc/ide/ide? .............................................................................. File Content channel IDE channel (0 or 1) @@ -486,11 +538,11 @@ Table 1-4: IDE controller info in /proc/ide/ide? .............................................................................. Each device connected to a controller has a separate subdirectory in the -controllers directory. The files listed in table 1-5 are contained in these +controllers directory. The files listed in table 1-6 are contained in these directories. -Table 1-5: IDE device information +Table 1-6: IDE device information .............................................................................. File Content cache The cache @@ -1014,6 +1066,13 @@ check the amount of free space (value is in seconds). Default settings are: 4, resume it if we have a value of 3 or more percent; consider information about the amount of free space valid for 30 seconds +audit_argv_kb +------------- + +The file contains a single value denoting the limit on the argv array size +for execve (in KiB). This limit is only applied when system call auditing for +execve is enabled, otherwise the value is ignored. + ctrl-alt-del ------------ @@ -1297,6 +1356,21 @@ nr_hugepages configures number of hugetlb page reserved for the system. hugetlb_shm_group contains group id that is allowed to create SysV shared memory segment using hugetlb page. +hugepages_treat_as_movable +-------------------------- + +This parameter is only useful when kernelcore= is specified at boot time to +create ZONE_MOVABLE for pages that may be reclaimed or migrated. Huge pages +are not movable so are not normally allocated from ZONE_MOVABLE. A non-zero +value written to hugepages_treat_as_movable allows huge pages to be allocated +from ZONE_MOVABLE. + +Once enabled, the ZONE_MOVABLE is treated as an area of memory the huge +pages pool can easily grow or shrink within. Assuming that applications are +not running that mlock() a lot of memory, it is likely the huge pages pool +can grow to the size of ZONE_MOVABLE by repeatedly entering the desired value +into nr_hugepages and triggering page reclaim. + laptop_mode ----------- @@ -2111,4 +2185,41 @@ those 64-bit counters, process A could see an intermediate result. More information about this can be found within the taskstats documentation in Documentation/accounting. +2.15 /proc/<pid>/coredump_filter - Core dump filtering settings +--------------------------------------------------------------- +When a process is dumped, all anonymous memory is written to a core file as +long as the size of the core file isn't limited. But sometimes we don't want +to dump some memory segments, for example, huge shared memory. Conversely, +sometimes we want to save file-backed memory segments into a core file, not +only the individual files. + +/proc/<pid>/coredump_filter allows you to customize which memory segments +will be dumped when the <pid> process is dumped. coredump_filter is a bitmask +of memory types. If a bit of the bitmask is set, memory segments of the +corresponding memory type are dumped, otherwise they are not dumped. + +The following 4 memory types are supported: + - (bit 0) anonymous private memory + - (bit 1) anonymous shared memory + - (bit 2) file-backed private memory + - (bit 3) file-backed shared memory + + Note that MMIO pages such as frame buffer are never dumped and vDSO pages + are always dumped regardless of the bitmask status. + +Default value of coredump_filter is 0x3; this means all anonymous memory +segments are dumped. + +If you don't want to dump all shared memory segments attached to pid 1234, +write 1 to the process's proc file. + + $ echo 0x1 > /proc/1234/coredump_filter + +When a new process is created, the process inherits the bitmask status from its +parent. It is useful to set up coredump_filter before the program runs. +For example: + + $ echo 0x7 > /proc/self/coredump_filter + $ ./some_program + ------------------------------------------------------------------------------ |