3 # Swap monitoring daemon. Every 30 seconds, checks process memory
4 # usage. At 90% utilization, resets the slice that is consuming the
5 # most physical memory. At 95% utilization, reboots the machine to
8 # Mark Huang <mlhuang@cs.princeton.edu>
9 # Andy Bavier <acb@cs.princeton.edu>
10 # Copyright (C) 2004-2006 The Trustees of Princeton University
12 # $Id: swapmon.py,v 1.2 2006/04/28 19:32:18 mlhuang Exp $
24 # util-vserver/python/vserver.py allows us to control slices directly
26 from vserver import VServer
28 # bwlimit exports a few useful functions like run(), get_xid(), and get_slice()
37 datafile = "/var/lib/misc/swapmon.dat"
39 # Seconds between process analysis
42 # Minimum change in swap utilization over 30 seconds that will trigger
43 # early process analysis.
46 # Swap utilization at which the largest consumer of physical memory is reset
49 # Swap utilization at which the machine is rebooted
52 # Minimum physical memory utilization to be considered the largest consumer
55 # System slices that should not be reset (regexps)
56 system_slices = ['root', PLC_SLICE_PREFIX + '_']
58 # Message sent after a critical reboot
59 rebooted_subject = "pl_mom rebooted %(hostname)s"
62 Sometime before %(date)s, swap space was
63 nearly exhausted on %(hostname)s, so pl_mom rebooted it.
65 Slices active prior to reboot are listed below. Memory usage
66 statistics are not entirely accurate due to threading.
70 %(date)s %(hostname)s reboot
73 # Message sent after a hog is reset
74 reset_subject = "pl_mom reset slice %(slice)s on %(hostname)s"
77 Sometime before %(date)s, swap space was
78 nearly exhausted on %(hostname)s.
80 Slice %(slice)s was reset since it was the largest consumer of
81 physical memory at %(rss)s (%(percent)4.1f%%).
83 Please reply to this message explaining the nature of your experiment,
84 and what you are doing to address the problem.
86 %(slice)s processes prior to reset:
90 %(date)s %(hostname)s reset %(slice)s
93 # Message sent to system slices that should not be reset
94 alarm_subject = "pl_mom alarm slice %(slice)s on %(hostname)s"
97 Sometime before %(date)s, swap space was
98 nearly exhausted on %(hostname)s.
100 System slice %(slice)s was the largest consumer of physical memory at
101 %(rss)s (%(percent)4.1f%%). It was not reset, but please verify its
104 %(slice)s processes prior to alarm:
108 %(date)s %(hostname)s alarm %(slice)s
113 Usage: %s [OPTIONS]...
116 -d, --debug Enable debugging (default: %s)
117 -v, --verbose Increase verbosity level (default: %d)
118 -f, --file=FILE Data file (default: %s)
119 -s, --slice=SLICE Constrain monitoring to these slices (default: all)
120 -p, --period=SECONDS Seconds between normal process analysis (default: %s)
121 --reset-thresh=PERCENT Swap utilization at which slice reset is attempted
122 --reboot-thresh=PERCENT Swap utilization at which the machine is rebooted
123 --min-thresh=PERCENT Minimum physical memory utilization to be considered a hog
124 --system-slice=SLICE System slice that should not be reset
125 --status Print memory usage statistics and exit
126 -h, --help This message
127 """.lstrip() % (sys.argv[0], debug, verbose, datafile, format_period(period))
129 def slicestat(names = None):
131 Get status of specified slices (if names is None or empty, all
132 slices). vsize and rss are in KiB. Returns
134 {xid: {'xid': slice_id,
136 'procs': [{'pid': pid, 'xid': slice_id, 'user', username, 'cmd': command,
137 'vsize': virtual_kib, 'rss': physical_kib,
138 'pcpu': cpu_percent, 'pmem': mem_percent}]
139 'vsize': total_virtual_kib,
140 'rss': total_physical_kib}}
143 # Mandatory fields. xid is a virtual field inserted by vps. Make
144 # sure cmd is last so that it does not get truncated
146 fields = ['pid', 'xid', 'user', 'vsize', 'rss', 'pcpu', 'pmem', 'cmd']
148 # vps inserts xid after pid in the output, but ps doesn't know
149 # what the field means.
150 ps_fields = list(fields)
151 ps_fields.remove('xid')
155 # Eat the header line. vps depends on the header to figure out
156 # which column is the PID column, so we can't just tell ps not to
158 for line in bwlimit.run("/usr/sbin/vps -e -o " + ",".join(ps_fields))[1:]:
162 # Replace "0 MAIN" and "1 ALL_PROC" (the special monikers that
163 # vps uses to denote the root context and the "all contexts"
164 # context) with "0" so that we can just split() on whitespace.
165 line = line.replace("0 MAIN", "0").replace("1 ALL_PROC", "0")
167 # Represent process as a dict of fields
168 values = line.split(None, len(fields) - 1)
169 if len(values) != len(fields):
171 proc = dict(zip(fields, values))
173 # Convert ints and floats
176 proc[field] = int(proc[field])
179 proc[field] = float(proc[field])
183 # Assign (pl_)sshd processes to slice instead of root
184 m = re.search(r"sshd: ([a-zA-Z_]+)", proc['cmd'])
186 xid = bwlimit.get_xid(m.group(1))
190 name = bwlimit.get_slice(proc['xid'])
192 # Orphaned (not associated with a slice) class
193 name = "%d?" % proc['xid']
195 # Monitor only the specified slices
196 if names and name not in names:
199 # Additional overhead calculations from slicestat
201 # Include 12 KiB of process overhead =
202 # 4 KiB top-level page table +
203 # 4 KiB kernel structure +
204 # 4 KiB basic page table
207 # Include additional page table overhead
208 if proc['vsize'] > 4096:
209 proc['rss'] += 4 * ((proc['vsize'] - 1) / 4096)
211 if slices.has_key(proc['xid']):
212 slice = slices[proc['xid']]
214 slice = {'xid': proc['xid'], 'name': name, 'procs': [], 'vsize': 0, 'rss': 0}
216 slice['procs'].append(proc)
217 slice['vsize'] += proc['vsize']
218 slice['rss'] += proc['rss']
220 slices[proc['xid']] = slice
226 Returns total physical memory on the system in KiB.
229 meminfo = open("/proc/meminfo", "r")
230 line = meminfo.readline()
232 if line[0:8] == "MemTotal":
233 # MemTotal: 255396 kB
234 (name, value, kb) = line.split()
241 Returns swap utilization on the system as a whole percentage (0-100).
248 swaps = open("/proc/swaps", "r")
250 lines = swaps.readlines()[1:]
253 # /dev/mapper/planetlab-swap partition 1048568 3740 -1
254 (filename, type, size, used, priority) = line.strip().split()
256 total_swap += int(size)
257 total_used += int(used)
258 except ValueEror, err:
260 except (IOError, KeyError), err:
263 return 100 * total_used / total_swap
265 def summary(names = None, total_rss = memtotal()):
267 Return a summary of memory usage by slice.
269 slicelist = slicestat(names).values()
270 slicelist.sort(lambda a, b: b['rss'] - a['rss'])
272 table = "%-20s%10s%24s\n\n" % ("Slice", "Processes", "Memory Usage")
273 for slice in slicelist:
274 table += "%-20s%10d%16s (%4.1f%%)\n" % \
275 (slice['name'], len(slice['procs']),
276 format_bytes(slice['rss'] * 1024, si = False),
277 100. * slice['rss'] / total_rss)
283 global debug, verbose, datafile
284 global period, change_thresh, reset_thresh, reboot_thresh, min_thresh, system_slices
289 longopts = ["debug", "verbose", "file=", "slice=", "status", "help"]
290 longopts += ["period=", "reset-thresh=", "reboot-thresh=", "min-thresh=", "system-slice="]
291 (opts, argv) = getopt.getopt(sys.argv[1:], "dvf:s:ph", longopts)
292 except getopt.GetoptError, err:
293 print "Error: " + err.msg
297 for (opt, optval) in opts:
298 if opt == "-d" or opt == "--debug":
300 elif opt == "-v" or opt == "--verbose":
302 elif opt == "-f" or opt == "--file":
304 elif opt == "-s" or opt == "--slice":
306 elif opt == "-p" or opt == "--period":
308 elif opt == "--change-thresh":
309 change_thresh = int(optval)
310 elif opt == "--reset-thresh":
311 reset_thresh = int(optval)
312 elif opt == "--reboot-thresh":
313 reboot_thresh = int(optval)
314 elif opt == "--min-thresh":
315 min_thresh = int(optval)
316 elif opt == "--system-slice":
317 system_slices.append(optval)
318 elif opt == "--status":
325 # Check if we are already running
332 # Redirect stdout and stderr to syslog
333 syslog.openlog("swapmon")
334 sys.stdout = sys.stderr = Logger()
336 # Get total physical memory
337 total_rss = memtotal()
340 f = open(datafile, "r+")
342 print "Loading %s" % datafile
343 (version, slices) = pickle.load(f)
345 # Check version of data file
346 if version != "$Id: swapmon.py,v 1.2 2006/04/28 19:32:18 mlhuang Exp $":
347 print "Not using old version '%s' data file %s" % (version, datafile)
350 params = {'hostname': socket.gethostname(),
351 'date': time.asctime(time.gmtime()) + " GMT",
352 'table': summary(total_rss)}
355 print rebooted_subject % params
356 print rebooted_body % params
358 slicemail(None, rebooted_subject % params, rebooted_body % params)
363 version = "$Id: swapmon.py,v 1.2 2006/04/28 19:32:18 mlhuang Exp $"
366 # Query process table every 30 seconds, or when a large change in
367 # swap utilization is detected.
372 # System slices that we have warned but could not reset
377 if last_used is None:
380 print "%d%% swap consumed" % used
382 if used >= reboot_thresh:
383 # Dump slice state before rebooting
385 print "Saving %s" % datafile
386 f = open(datafile, "w")
387 pickle.dump((version, slices), f)
390 # Goodbye, cruel world
391 print "%d%% swap consumed, rebooting" % used
393 bwlimit.run("/bin/sync; /sbin/reboot -f")
395 elif used >= reset_thresh:
397 slicelist = slices.values()
398 slicelist.sort(lambda a, b: b['rss'] - a['rss'])
399 for slice in slicelist:
400 percent = 100. * slice['rss'] / total_rss
401 if percent < min_thresh:
404 print "%d%% swap consumed, slice %s is using %s (%d%%) of memory" % \
407 format_bytes(slice['rss'] * 1024, si = False),
410 slice['procs'].sort(lambda a, b: b['rss'] - a['rss'])
412 table = "%5s %10s %10s %4s %4s %s\n\n" % ("PID", "VIRT", "RES", '%CPU', '%MEM', 'COMMAND')
413 for proc in slice['procs']:
414 table += "%5s %10s %10s %4.1f %4.1f %s\n" % \
416 format_bytes(proc['vsize'] * 1024, si = False),
417 format_bytes(proc['rss'] * 1024, si = False),
418 proc['pcpu'], proc['pmem'], proc['cmd'])
420 params = {'hostname': socket.gethostname(),
421 'date': time.asctime(time.gmtime()) + " GMT",
423 'slice': slice['name'],
424 'rss': format_bytes(slice['rss'] * 1024, si = False),
427 # Match slice name against system slice patterns
428 is_system_slice = filter(None, [re.match(pattern, slice['name']) for pattern in system_slices])
431 # Do not reset system slices, just warn once
432 if slice['name'] not in warned:
433 warned.append(slice['name'])
435 print alarm_subject % params
436 print alarm_body % params
438 print "Warning slice " + slice['name']
439 slicemail(slice['name'], alarm_subject % params, alarm_body % params)
443 print reset_subject % params
444 print reset_body % params
449 print "Resetting slice " + slice['name']
450 vserver = VServer(slice['name'])
452 vserver.start(wait = False)
456 except Exception, err:
457 print "Warning: Exception received while resetting slice %s:" % slice['name'], err
458 slicemail(slice['name'], reset_subject % params, reset_body % params)
461 elif timer <= 0 or used >= (last_used + change_thresh):
462 if used >= (last_used + change_thresh):
463 print "%d%% swap consumed, %d%% in last %d seconds" % \
464 (used, used - last_used, period - timer)
466 slices = slicestat(names)
469 # Keep track of large changes in swap utilization
477 if __name__ == '__main__':