--- /dev/null
+#!/usr/bin/python
+#
+# Swap monitoring daemon. Every 30 seconds, checks process memory
+# usage. At 90% utilization, resets the slice that is consuming the
+# most physical memory. At 95% utilization, reboots the machine to
+# avoid a crash.
+#
+# Mark Huang <mlhuang@cs.princeton.edu>
+# Andy Bavier <acb@cs.princeton.edu>
+# Copyright (C) 2004-2006 The Trustees of Princeton University
+#
+# $Id: BandwidthMonitor.py,v 1.1 2006/04/25 14:40:28 mlhuang Exp $
+#
+
+import syslog
+import os
+import sys
+import getopt
+import re
+import pickle
+import socket
+import time
+
+import textwrap
+wrap = textwrap.TextWrapper()
+
+# util-vserver/python/vserver.py allows us to control slices directly
+# from Python
+from vserver import VServer
+
+# bwlimit exports a few useful functions like run(), get_xid(), and get_slice()
+import bwlimit
+
+# Utility functions
+from pl_mom import *
+
+# Defaults
+debug = False
+verbose = 0
+datafile = "/var/lib/misc/swapmon.dat"
+
+# Seconds between process analysis
+period = 30
+
+# Minimum change in swap utilization over 30 seconds that will trigger
+# early process analysis.
+change_thresh = 5
+
+# Swap utilization at which the largest consumer of physical memory is reset
+reset_thresh = 85
+
+# Swap utilization at which the machine is rebooted
+reboot_thresh = 95
+
+# Minimum physical memory utilization to be considered the largest consumer
+min_thresh = 10
+
+# System slices that should not be reset (regexps)
+system_slices = ['root', PLC_SLICE_PREFIX + '_']
+
+# Message sent after a critical reboot
+rebooted_subject = "pl_mom rebooted %(hostname)s"
+rebooted_body = \
+"""
+Sometime before %(date)s, swap space was
+nearly exhausted on %(hostname)s, so pl_mom rebooted it.
+
+Slices active prior to reboot are listed below. Memory usage
+statistics are not entirely accurate due to threading.
+
+%(table)s
+
+%(date)s %(hostname)s reboot
+""".lstrip()
+
+# Message sent after a hog is reset
+reset_subject = "pl_mom reset slice %(slice)s on %(hostname)s"
+reset_body = \
+"""
+Sometime before %(date)s, swap space was
+nearly exhausted on %(hostname)s.
+
+Slice %(slice)s was reset since it was the largest consumer of
+physical memory at %(rss)s (%(percent)4.1f%%).
+
+Please reply to this message explaining the nature of your experiment,
+and what you are doing to address the problem.
+
+%(slice)s processes prior to reset:
+
+%(table)s
+
+%(date)s %(hostname)s reset %(slice)s
+""".lstrip()
+
+# Message sent to system slices that should not be reset
+alarm_subject = "pl_mom alarm slice %(slice)s on %(hostname)s"
+alarm_body = \
+"""
+Sometime before %(date)s, swap space was
+nearly exhausted on %(hostname)s.
+
+System slice %(slice)s was the largest consumer of physical memory at
+%(rss)s (%(percent)4.1f%%). It was not reset, but please verify its
+behavior.
+
+%(slice)s processes prior to alarm:
+
+%(table)s
+
+%(date)s %(hostname)s alarm %(slice)s
+""".lstrip()
+
+def usage():
+ print """
+Usage: %s [OPTIONS]...
+
+Options:
+ -d, --debug Enable debugging (default: %s)
+ -v, --verbose Increase verbosity level (default: %d)
+ -f, --file=FILE Data file (default: %s)
+ -s, --slice=SLICE Constrain monitoring to these slices (default: all)
+ -p, --period=SECONDS Seconds between normal process analysis (default: %s)
+ --reset-thresh=PERCENT Swap utilization at which slice reset is attempted
+ --reboot-thresh=PERCENT Swap utilization at which the machine is rebooted
+ --min-thresh=PERCENT Minimum physical memory utilization to be considered a hog
+ --system-slice=SLICE System slice that should not be reset
+ -h, --help This message
+""".lstrip() % (sys.argv[0], debug, verbose, datafile, format_period(period))
+
+def slicestat(names = None):
+ """
+ Get status of specified slices (if names is None or empty, all
+ slices). vsize and rss are in KiB. Returns
+
+ {xid: {'xid': slice_id,
+ 'name': slice_name,
+ 'procs': [{'pid': pid, 'xid': slice_id, 'user', username, 'cmd': command,
+ 'vsize': virtual_kib, 'rss': physical_kib,
+ 'pcpu': cpu_percent, 'pmem': mem_percent}]
+ 'vsize': total_virtual_kib,
+ 'rss': total_physical_kib}}
+ """
+
+ # Mandatory fields. xid is a virtual field inserted by vps. Make
+ # sure cmd is last so that it does not get truncated
+ # automatically.
+ fields = ['pid', 'xid', 'user', 'vsize', 'rss', 'pcpu', 'pmem', 'cmd']
+
+ # vps inserts xid after pid in the output, but ps doesn't know
+ # what the field means.
+ ps_fields = list(fields)
+ ps_fields.remove('xid')
+
+ slices = {}
+
+ # Eat the header line. vps depends on the header to figure out
+ # which column is the PID column, so we can't just tell ps not to
+ # print it.
+ for line in bwlimit.run("/usr/sbin/vps -e -o " + ",".join(ps_fields))[1:]:
+ # Chomp newline
+ line = line.strip()
+
+ # Replace "0 MAIN" and "1 ALL_PROC" (the special monikers that
+ # vps uses to denote the root context and the "all contexts"
+ # context) with "0" so that we can just split() on whitespace.
+ line = line.replace("0 MAIN", "0").replace("1 ALL_PROC", "0")
+
+ # Represent process as a dict of fields
+ values = line.split(None, len(fields) - 1)
+ if len(values) != len(fields):
+ continue
+ proc = dict(zip(fields, values))
+
+ # Convert ints and floats
+ for field in proc:
+ try:
+ proc[field] = int(proc[field])
+ except ValueError:
+ try:
+ proc[field] = float(proc[field])
+ except ValueError:
+ pass
+
+ # Assign (pl_)sshd processes to slice instead of root
+ m = re.search(r"sshd: ([a-zA-Z_]+)", proc['cmd'])
+ if m is not None:
+ xid = bwlimit.get_xid(m.group(1))
+ if xid is not None:
+ proc['xid'] = xid
+
+ name = bwlimit.get_slice(proc['xid'])
+ if name is None:
+ # Orphaned (not associated with a slice) class
+ name = "%d?" % proc['xid']
+
+ # Monitor only the specified slices
+ if names and name not in names:
+ continue
+
+ # Additional overhead calculations from slicestat
+
+ # Include 12 KiB of process overhead =
+ # 4 KiB top-level page table +
+ # 4 KiB kernel structure +
+ # 4 KiB basic page table
+ proc['rss'] += 12
+
+ # Include additional page table overhead
+ if proc['vsize'] > 4096:
+ proc['rss'] += 4 * ((proc['vsize'] - 1) / 4096)
+
+ if slices.has_key(proc['xid']):
+ slice = slices[proc['xid']]
+ else:
+ slice = {'xid': proc['xid'], 'name': name, 'procs': [], 'vsize': 0, 'rss': 0}
+
+ slice['procs'].append(proc)
+ slice['vsize'] += proc['vsize']
+ slice['rss'] += proc['rss']
+
+ slices[proc['xid']] = slice
+
+ return slices
+
+def memtotal():
+ """
+ Returns total physical memory on the system in KiB.
+ """
+
+ meminfo = open("/proc/meminfo", "r")
+ line = meminfo.readline()
+ meminfo.close()
+ if line[0:8] == "MemTotal":
+ # MemTotal: 255396 kB
+ (name, value, kb) = line.split()
+ return int(value)
+
+ return 0
+
+def swap_used():
+ """
+ Returns swap utilization on the system as a whole percentage (0-100).
+ """
+
+ total_swap = 0
+ total_used = 0
+
+ try:
+ swaps = open("/proc/swaps", "r")
+ # Eat header line
+ lines = swaps.readlines()[1:]
+ swaps.close()
+ for line in lines:
+ # /dev/mapper/planetlab-swap partition 1048568 3740 -1
+ (filename, type, size, used, priority) = line.strip().split()
+ try:
+ total_swap += int(size)
+ total_used += int(used)
+ except ValueEror, err:
+ pass
+ except (IOError, KeyError), err:
+ pass
+
+ return 100 * total_used / total_swap
+
+def main():
+ # Defaults
+ global debug, verbose, datafile
+ global period, change_thresh, reset_thresh, reboot_thresh, min_thresh, system_slices
+ # All slices
+ names = []
+
+ try:
+ longopts = ["debug", "verbose", "file=", "slice=", "help"]
+ longopts += ["period=", "reset-thresh=", "reboot-thresh=", "min-thresh=", "system-slice="]
+ (opts, argv) = getopt.getopt(sys.argv[1:], "dvf:s:ph", longopts)
+ except getopt.GetoptError, err:
+ print "Error: " + err.msg
+ usage()
+ sys.exit(1)
+
+ for (opt, optval) in opts:
+ if opt == "-d" or opt == "--debug":
+ debug = True
+ elif opt == "-v" or opt == "--verbose":
+ verbose += 1
+ elif opt == "-f" or opt == "--file":
+ datafile = optval
+ elif opt == "-s" or opt == "--slice":
+ names.append(optval)
+ elif opt == "-p" or opt == "--period":
+ period = int(optval)
+ elif opt == "--change-thresh":
+ change_thresh = int(optval)
+ elif opt == "--reset-thresh":
+ reset_thresh = int(optval)
+ elif opt == "--reboot-thresh":
+ reboot_thresh = int(optval)
+ elif opt == "--min-thresh":
+ min_thresh = int(optval)
+ elif opt == "--system-slice":
+ system_slices.append(optval)
+ else:
+ usage()
+ sys.exit(0)
+
+ # Check if we are already running
+ writepid("swapmon")
+
+ if not debug:
+ daemonize()
+ # Rewrite PID file
+ writepid("swapmon")
+ # Redirect stdout and stderr to syslog
+ syslog.openlog("swapmon")
+ sys.stdout = sys.stderr = Logger()
+
+ # Get total physical memory
+ total_rss = memtotal()
+
+ try:
+ f = open(datafile, "r+")
+ if verbose:
+ print "Loading %s" % datafile
+ (version, slices) = pickle.load(f)
+ f.close()
+ # Check version of data file
+ if version != "$Id: bwmon.py,v 1.1 2006/04/25 14:40:28 mlhuang Exp $":
+ print "Not using old version '%s' data file %s" % (version, datafile)
+ raise Exception
+
+ # Send notification if we rebooted the node because of swap exhaustion
+ slicelist = slices.values()
+ slicelist.sort(lambda a, b: b['rss'] - a['rss'])
+
+ table = "%-20s%10s%24s\n\n" % ("Slice", "Processes", "Memory Usage")
+ for slice in slicelist:
+ table += "%-20s%10d%16s (%4.1f%%)\n" % \
+ (slice['name'], len(slice['procs']),
+ format_bytes(slice['rss'] * 1024, si = False),
+ 100. * slice['rss'] / total_rss)
+
+ params = {'hostname': socket.gethostname(),
+ 'date': time.asctime(time.gmtime()) + " GMT",
+ 'table': table}
+
+ if debug:
+ print rebooted_subject % params
+ print rebooted_body % params
+ else:
+ slicemail(None, rebooted_subject % params, rebooted_body % params)
+
+ # Delete data file
+ os.unlink(datafile)
+ except Exception:
+ version = "$Id: bwmon.py,v 1.1 2006/04/25 14:40:28 mlhuang Exp $"
+ slices = {}
+
+ # Query process table every 30 seconds, or when a large change in
+ # swap utilization is detected.
+ timer = period
+ last_used = None
+ used = None
+
+ # System slices that we have warned but could not reset
+ warned = []
+
+ while True:
+ used = swap_used()
+ if last_used is None:
+ last_used = used
+ if verbose:
+ print "%d%% swap consumed" % used
+
+ if used >= reboot_thresh:
+ # Dump slice state before rebooting
+ if verbose:
+ print "Saving %s" % datafile
+ f = open(datafile, "w")
+ pickle.dump((version, slices), f)
+ f.close()
+
+ # Goodbye, cruel world
+ print "%d%% swap consumed, rebooting" % used
+ if not debug:
+ bwlimit.run("/bin/sync; /sbin/reboot -f")
+
+ elif used >= reset_thresh:
+ # Try and find a hog
+ slicelist = slices.values()
+ slicelist.sort(lambda a, b: b['rss'] - a['rss'])
+ for slice in slicelist:
+ percent = 100. * slice['rss'] / total_rss
+ if percent < min_thresh:
+ continue
+
+ print "%d%% swap consumed, slice %s is using %s (%d%%) of memory" % \
+ (used,
+ slice['name'],
+ format_bytes(slice['rss'] * 1024, si = False),
+ percent)
+
+ slice['procs'].sort(lambda a, b: b['rss'] - a['rss'])
+
+ table = "%5s %10s %10s %4s %4s %s\n\n" % ("PID", "VIRT", "RES", '%CPU', '%MEM', 'COMMAND')
+ for proc in slice['procs']:
+ table += "%5s %10s %10s %4.1f %4.1f %s\n" % \
+ (proc['pid'],
+ format_bytes(proc['vsize'] * 1024, si = False),
+ format_bytes(proc['rss'] * 1024, si = False),
+ proc['pcpu'], proc['pmem'], proc['cmd'])
+
+ params = {'hostname': socket.gethostname(),
+ 'date': time.asctime(time.gmtime()) + " GMT",
+ 'table': table,
+ 'slice': slice['name'],
+ 'rss': format_bytes(slice['rss'] * 1024, si = False),
+ 'percent': percent}
+
+ # Match slice name against system slice patterns
+ is_system_slice = filter(None, [re.match(pattern, slice['name']) for pattern in system_slices])
+
+ if is_system_slice:
+ # Do not reset system slices, just warn once
+ if slice['name'] not in warned:
+ warned.append(slice['name'])
+ if debug:
+ print alarm_subject % params
+ print alarm_body % params
+ else:
+ print "Warning slice " + slice['name']
+ slicemail(slice['name'], alarm_subject % params, alarm_body % params)
+ else:
+ # Otherwise, reset
+ if debug:
+ print reset_subject % params
+ print reset_body % params
+ else:
+ try:
+ pid = os.fork()
+ if pid == 0:
+ print "Resetting slice " + slice['name']
+ vserver = VServer(slice['name'])
+ vserver.stop()
+ vserver.start(wait = False)
+ os._exit(0)
+ else:
+ os.waitpid(pid, 0)
+ except Exception, err:
+ print "Warning: Exception received while resetting slice %s:" % slice['name'], err
+ slicemail(slice['name'], reset_subject % params, reset_body % params)
+ break
+
+ elif timer <= 0 or used >= (last_used + change_thresh):
+ if used >= (last_used + change_thresh):
+ print "%d%% swap consumed, %d%% in last %d seconds" % \
+ (used, used - last_used, period - timer)
+ # Get slice state
+ slices = slicestat(names)
+ # Reset timer
+ timer = period
+ # Keep track of large changes in swap utilization
+ last_used = used
+
+ timer -= 1
+ time.sleep(1)
+
+ removepid("swapmon")
+
+if __name__ == '__main__':
+ main()