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@harpo
Created May 12, 2014 13:34
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  1. harpo created this gist May 12, 2014.
    473 changes: 473 additions & 0 deletions ps_mem.py
    Original file line number Diff line number Diff line change
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    #!/usr/bin/env python

    # Try to determine how much RAM is currently being used per program.
    # Note per _program_, not per process. So for example this script
    # will report RAM used by all httpd process together. In detail it reports:
    # sum(private RAM for program processes) + sum(Shared RAM for program processes)
    # The shared RAM is problematic to calculate, and this script automatically
    # selects the most accurate method available for your kernel.

    # Licence: LGPLv2
    # Author: [email protected]
    # Source: http://www.pixelbeat.org/scripts/ps_mem.py

    # V1.0 06 Jul 2005 Initial release
    # V1.1 11 Aug 2006 root permission required for accuracy
    # V1.2 08 Nov 2006 Add total to output
    # Use KiB,MiB,... for units rather than K,M,...
    # V1.3 22 Nov 2006 Ignore shared col from /proc/$pid/statm for
    # 2.6 kernels up to and including 2.6.9.
    # There it represented the total file backed extent
    # V1.4 23 Nov 2006 Remove total from output as it's meaningless
    # (the shared values overlap with other programs).
    # Display the shared column. This extra info is
    # useful, especially as it overlaps between programs.
    # V1.5 26 Mar 2007 Remove redundant recursion from human()
    # V1.6 05 Jun 2007 Also report number of processes with a given name.
    # Patch from [email protected]
    # V1.7 20 Sep 2007 Use PSS from /proc/$pid/smaps if available, which
    # fixes some over-estimation and allows totalling.
    # Enumerate the PIDs directly rather than using ps,
    # which fixes the possible race between reading
    # RSS with ps, and shared memory with this program.
    # Also we can show non truncated command names.
    # V1.8 28 Sep 2007 More accurate matching for stats in /proc/$pid/smaps
    # as otherwise could match libraries causing a crash.
    # Patch from [email protected]
    # V1.9 20 Feb 2008 Fix invalid values reported when PSS is available.
    # Reported by Andrey Borzenkov <[email protected]>
    # V3.1 10 May 2013
    # http://github.com/pixelb/scripts/commits/master/scripts/ps_mem.py

    # Notes:
    #
    # All interpreted programs where the interpreter is started
    # by the shell or with env, will be merged to the interpreter
    # (as that's what's given to exec). For e.g. all python programs
    # starting with "#!/usr/bin/env python" will be grouped under python.
    # You can change this by using the full command line but that will
    # have the undesirable affect of splitting up programs started with
    # differing parameters (for e.g. mingetty tty[1-6]).
    #
    # For 2.6 kernels up to and including 2.6.13 and later 2.4 redhat kernels
    # (rmap vm without smaps) it can not be accurately determined how many pages
    # are shared between processes in general or within a program in our case:
    # http://lkml.org/lkml/2005/7/6/250
    # A warning is printed if overestimation is possible.
    # In addition for 2.6 kernels up to 2.6.9 inclusive, the shared
    # value in /proc/$pid/statm is the total file-backed extent of a process.
    # We ignore that, introducing more overestimation, again printing a warning.
    # Since kernel 2.6.23-rc8-mm1 PSS is available in smaps, which allows
    # us to calculate a more accurate value for the total RAM used by programs.
    #
    # Programs that use CLONE_VM without CLONE_THREAD are discounted by assuming
    # they're the only programs that have the same /proc/$PID/smaps file for
    # each instance. This will fail if there are multiple real instances of a
    # program that then use CLONE_VM without CLONE_THREAD, or if a clone changes
    # its memory map while we're checksumming each /proc/$PID/smaps.
    #
    # I don't take account of memory allocated for a program
    # by other programs. For e.g. memory used in the X server for
    # a program could be determined, but is not.
    #
    # FreeBSD is supported if linprocfs is mounted at /compat/linux/proc/
    # FreeBSD 8.0 supports up to a level of Linux 2.6.16

    import getopt
    import time
    import errno
    import os
    import sys

    try:
    # md5 module is deprecated on python 2.6
    # so try the newer hashlib first
    import hashlib
    md5_new = hashlib.md5
    except ImportError:
    import md5
    md5_new = md5.new


    # The following exits cleanly on Ctrl-C or EPIPE
    # while treating other exceptions as before.
    def std_exceptions(etype, value, tb):
    sys.excepthook = sys.__excepthook__
    if issubclass(etype, KeyboardInterrupt):
    pass
    elif issubclass(etype, IOError) and value.errno == errno.EPIPE:
    pass
    else:
    sys.__excepthook__(etype, value, tb)
    sys.excepthook = std_exceptions

    #
    # Define some global variables
    #

    PAGESIZE = os.sysconf("SC_PAGE_SIZE") / 1024 #KiB
    our_pid = os.getpid()

    have_pss = 0

    class Proc:
    def __init__(self):
    uname = os.uname()
    if uname[0] == "FreeBSD":
    self.proc = '/compat/linux/proc'
    else:
    self.proc = '/proc'

    def path(self, *args):
    return os.path.join(self.proc, *(str(a) for a in args))

    def open(self, *args):
    try:
    return open(self.path(*args))
    except (IOError, OSError):
    val = sys.exc_info()[1]
    if (val.errno == errno.ENOENT or # kernel thread or process gone
    val.errno == errno.EPERM):
    raise LookupError

    proc = Proc()


    #
    # Functions
    #

    def parse_options():
    try:
    long_options = ['split-args', 'help']
    opts, args = getopt.getopt(sys.argv[1:], "shp:w:", long_options)
    except getopt.GetoptError:
    sys.stderr.write(help())
    sys.exit(3)

    # ps_mem.py options
    split_args = False
    pids_to_show = None
    watch = None

    for o, a in opts:
    if o in ('-s', '--split-args'):
    split_args = True
    if o in ('-h', '--help'):
    sys.stdout.write(help())
    sys.exit(0)
    if o in ('-p',):
    try:
    pids_to_show = [int(x) for x in a.split(',')]
    except:
    sys.stderr.write(help())
    sys.exit(3)
    if o in ('-w',):
    try:
    watch = int(a)
    except:
    sys.stderr.write(help())
    sys.exit(3)

    return (split_args, pids_to_show, watch)

    def help():
    help_msg = 'ps_mem.py - Show process memory usage\n'\
    '\n'\
    '-h Show this help\n'\
    '-w <N> Measure and show process memory every N seconds\n'\
    '-p <pid>[,pid2,...pidN] Only show memory usage PIDs in the specified list\n' \
    '-s, --split-args Show and separate by, all command line arguments\n'

    return help_msg

    #(major,minor,release)
    def kernel_ver():
    kv = proc.open('sys/kernel/osrelease').readline().split(".")[:3]
    last = len(kv)
    if last == 2:
    kv.append('0')
    last -= 1
    for char in "-_":
    kv[last] = kv[last].split(char)[0]
    try:
    int(kv[last])
    except:
    kv[last] = 0
    return (int(kv[0]), int(kv[1]), int(kv[2]))


    #return Private,Shared
    #Note shared is always a subset of rss (trs is not always)
    def getMemStats(pid):
    global have_pss
    mem_id = pid #unique
    Private_lines = []
    Shared_lines = []
    Pss_lines = []
    Rss = (int(proc.open(pid, 'statm').readline().split()[1])
    * PAGESIZE)
    if os.path.exists(proc.path(pid, 'smaps')): #stat
    digester = md5_new()
    for line in proc.open(pid, 'smaps').readlines(): #open
    # Note we checksum smaps as maps is usually but
    # not always different for separate processes.
    digester.update(line.encode('latin1'))
    if line.startswith("Shared"):
    Shared_lines.append(line)
    elif line.startswith("Private"):
    Private_lines.append(line)
    elif line.startswith("Pss"):
    have_pss = 1
    Pss_lines.append(line)
    mem_id = digester.hexdigest()
    Shared = sum([int(line.split()[1]) for line in Shared_lines])
    Private = sum([int(line.split()[1]) for line in Private_lines])
    #Note Shared + Private = Rss above
    #The Rss in smaps includes video card mem etc.
    if have_pss:
    pss_adjust = 0.5 # add 0.5KiB as this avg error due to trunctation
    Pss = sum([float(line.split()[1])+pss_adjust for line in Pss_lines])
    Shared = Pss - Private
    elif (2,6,1) <= kernel_ver() <= (2,6,9):
    Shared = 0 #lots of overestimation, but what can we do?
    Private = Rss
    else:
    Shared = int(proc.open(pid, 'statm').readline().split()[2])
    Shared *= PAGESIZE
    Private = Rss - Shared
    return (Private, Shared, mem_id)


    def getCmdName(pid, split_args):
    cmdline = proc.open(pid, 'cmdline').read().split("\0")
    if cmdline[-1] == '' and len(cmdline) > 1:
    cmdline = cmdline[:-1]

    path = proc.path(pid, 'exe')
    try:
    path = os.readlink(path)
    # Some symlink targets were seen to contain NULs on RHEL 5 at least
    # https://github.com/pixelb/scripts/pull/10, so take string up to NUL
    path = path.split('\0')[0]
    except OSError:
    val = sys.exc_info()[1]
    if (val.errno == errno.ENOENT or # either kernel thread or process gone
    val.errno == errno.EPERM):
    raise LookupError

    if split_args:
    return " ".join(cmdline)
    if path.endswith(" (deleted)"):
    path = path[:-10]
    if os.path.exists(path):
    path += " [updated]"
    else:
    #The path could be have prelink stuff so try cmdline
    #which might have the full path present. This helped for:
    #/usr/libexec/notification-area-applet.#prelink#.fX7LCT (deleted)
    if os.path.exists(cmdline[0]):
    path = cmdline[0] + " [updated]"
    else:
    path += " [deleted]"
    exe = os.path.basename(path)
    cmd = proc.open(pid, 'status').readline()[6:-1]
    if exe.startswith(cmd):
    cmd = exe #show non truncated version
    #Note because we show the non truncated name
    #one can have separated programs as follows:
    #584.0 KiB + 1.0 MiB = 1.6 MiB mozilla-thunder (exe -> bash)
    # 56.0 MiB + 22.2 MiB = 78.2 MiB mozilla-thunderbird-bin
    return cmd


    #The following matches "du -h" output
    #see also human.py
    def human(num, power="Ki"):
    powers = ["Ki", "Mi", "Gi", "Ti"]
    while num >= 1000: #4 digits
    num /= 1024.0
    power = powers[powers.index(power)+1]
    return "%.1f %s" % (num, power)


    def cmd_with_count(cmd, count):
    if count > 1:
    return "%s (%u)" % (cmd, count)
    else:
    return cmd

    #Warn of possible inaccuracies
    #2 = accurate & can total
    #1 = accurate only considering each process in isolation
    #0 = some shared mem not reported
    #-1= all shared mem not reported
    def shared_val_accuracy():
    """http://wiki.apache.org/spamassassin/TopSharedMemoryBug"""
    kv = kernel_ver()
    if kv[:2] == (2,4):
    if proc.open('meminfo').read().find("Inact_") == -1:
    return 1
    return 0
    elif kv[:2] == (2,6):
    pid = os.getpid()
    if os.path.exists(proc.path(pid, 'smaps')):
    if proc.open(pid, 'smaps').read().find("Pss:")!=-1:
    return 2
    else:
    return 1
    if (2,6,1) <= kv <= (2,6,9):
    return -1
    return 0
    elif kv[0] > 2:
    return 2
    else:
    return 1

    def show_shared_val_accuracy( possible_inacc ):
    if possible_inacc == -1:
    sys.stderr.write(
    "Warning: Shared memory is not reported by this system.\n"
    )
    sys.stderr.write(
    "Values reported will be too large, and totals are not reported\n"
    )
    elif possible_inacc == 0:
    sys.stderr.write(
    "Warning: Shared memory is not reported accurately by this system.\n"
    )
    sys.stderr.write(
    "Values reported could be too large, and totals are not reported\n"
    )
    elif possible_inacc == 1:
    sys.stderr.write(
    "Warning: Shared memory is slightly over-estimated by this system\n"
    "for each program, so totals are not reported.\n"
    )
    sys.stderr.close()

    def get_memory_usage( pids_to_show, split_args, include_self=False, only_self=False ):
    cmds = {}
    shareds = {}
    mem_ids = {}
    count = {}
    for pid in os.listdir(proc.path('')):
    if not pid.isdigit():
    continue
    pid = int(pid)

    # Some filters
    if only_self and pid != our_pid:
    continue
    if pid == our_pid and not include_self:
    continue
    if pids_to_show is not None and pid not in pids_to_show:
    continue

    try:
    cmd = getCmdName(pid, split_args)
    except LookupError:
    #permission denied or
    #kernel threads don't have exe links or
    #process gone
    continue

    try:
    private, shared, mem_id = getMemStats(pid)
    except RuntimeError:
    continue #process gone
    if shareds.get(cmd):
    if have_pss: #add shared portion of PSS together
    shareds[cmd] += shared
    elif shareds[cmd] < shared: #just take largest shared val
    shareds[cmd] = shared
    else:
    shareds[cmd] = shared
    cmds[cmd] = cmds.setdefault(cmd, 0) + private
    if cmd in count:
    count[cmd] += 1
    else:
    count[cmd] = 1
    mem_ids.setdefault(cmd, {}).update({mem_id:None})

    #Add shared mem for each program
    total = 0
    for cmd in cmds:
    cmd_count = count[cmd]
    if len(mem_ids[cmd]) == 1 and cmd_count > 1:
    # Assume this program is using CLONE_VM without CLONE_THREAD
    # so only account for one of the processes
    cmds[cmd] /= cmd_count
    if have_pss:
    shareds[cmd] /= cmd_count
    cmds[cmd] = cmds[cmd] + shareds[cmd]
    total += cmds[cmd] #valid if PSS available

    sorted_cmds = sorted(cmds.items(), key=lambda x:x[1])
    sorted_cmds = [x for x in sorted_cmds if x[1]]

    return sorted_cmds, shareds, count, total

    def print_header():
    sys.stdout.write(" Private + Shared = RAM used\tProgram\n\n")

    def print_memory_usage(sorted_cmds, shareds, count, total):
    for cmd in sorted_cmds:
    sys.stdout.write("%8sB + %8sB = %8sB\t%s\n" %
    (human(cmd[1]-shareds[cmd[0]]),
    human(shareds[cmd[0]]), human(cmd[1]),
    cmd_with_count(cmd[0], count[cmd[0]])))
    if have_pss:
    sys.stdout.write("%s\n%s%8sB\n%s\n" %
    ("-" * 33, " " * 24, human(total), "=" * 33))

    def verify_environment():
    if os.geteuid() != 0:
    sys.stderr.write("Sorry, root permission required.\n")
    if __name__ == '__main__':
    sys.stderr.close()
    sys.exit(1)

    try:
    kv = kernel_ver()
    except (IOError, OSError):
    val = sys.exc_info()[1]
    if val.errno == errno.ENOENT:
    sys.stderr.write(
    "Couldn't access " + proc.path('') + "\n"
    "Only GNU/Linux and FreeBSD (with linprocfs) are supported\n")
    sys.exit(2)
    else:
    raise

    if __name__ == '__main__':
    verify_environment()
    split_args, pids_to_show, watch = parse_options()

    print_header()

    if watch is not None:
    try:
    sorted_cmds = True
    while sorted_cmds:
    sorted_cmds, shareds, count, total = get_memory_usage( pids_to_show, split_args )
    print_memory_usage(sorted_cmds, shareds, count, total)
    time.sleep(watch)
    else:
    sys.stdout.write('Process does not exist anymore.\n')
    except KeyboardInterrupt:
    pass
    else:
    # This is the default behavior
    sorted_cmds, shareds, count, total = get_memory_usage( pids_to_show, split_args )
    print_memory_usage(sorted_cmds, shareds, count, total)


    # We must close explicitly, so that any EPIPE exception
    # is handled by our excepthook, rather than the default
    # one which is reenabled after this script finishes.
    sys.stdout.close()

    vm_accuracy = shared_val_accuracy()
    show_shared_val_accuracy( vm_accuracy )