File "/usr/lib/python2.6/atexit.py", line 24, in _run_exitfuncs

Thu Jan 13 05:28:12 EST 2011

Hello!
I wrote a python (2.6) deamon running on linux. Program (deamon,
manager) collects lets say work-orders from db and creates sub-
processes for each one. Sub-processes do their job with out problems,
errors, exceptions. However, sometimes deamon throws:
Traceback (most recent call last):
 File "/usr/lib/python2.6/atexit.py", line 24, in _run_exitfuncs
 func(*targs, **kargs)
 File "/usr/lib/python2.6/multiprocessing/util.py", line 281, in
_exit_function
 p.join()
 File "/usr/lib/python2.6/multiprocessing/process.py", line 119, in
join
 res = self._popen.wait(timeout)
 File "/usr/lib/python2.6/multiprocessing/forking.py", line 117, in
wait
 return self.poll(0)
 File "/usr/lib/python2.6/multiprocessing/forking.py", line 106, in
poll
 pid, sts = os.waitpid(self.pid, flag)
OSError: [Errno 4] Interrupted system call
the main deamon process crushes (after some time) and the sub-
processes (childs) work fine until their work is finished.
below sample code that is responsible for creating sub_processes :
#!/usr/bin/python2.6
import pwd
import os
import sys
import time
import multiprocessing
import signal
import traceback
from deamon import deamon
from post import post
class manager(deamon):
 def __run_subprocess(self, typ, work_order):
 def runrun(t, z):
 self.__info('creating object post for %s' %(z))
			wns = post(z)
 self.__info('done creating object post for %s' %(z))
 #slownik z choiceem opcji
 choice = {'typ1': wns.typ1,
 'typ2': wns.typ2,
 'typ3': wns.typ3}
 if typ in choice:
 self.__info('lounching %s for %s' %(t, z))
 choice[typ]()
 else:
 self.__blad('nie znam %s typu operacji post, znam
tylko %s' \
 %(t, str(choice)))
 wns.endit()
 del(wns)
 self.__blad('problem with starting proces for =%s, typ=
%s' %(z, t))
 try:
 p = multiprocessing.Process(target=runrun,
args=(typ,work_order))
 self.__info('done preparing proces...')
 p.start()
 self.__info('done lounching process...doing join...')
 p.join()
 return p.pid
 except Exception, err:
 ex = sys.exc_info()
 sys.stderr.write(str(sys.exc_info()))
 msg = 'manager.__run_subprocess %s error in line %s'
 sys.stderr.write(msg %(str(err), ex[2].tb_lineno))
 #traceback.print_last()
 return None
 def __liczba_wierszy(self, active_child):
 return int(self._deamon__liczba_proces - active_child)
 def run(self):
 try:
 while True:
 active_child = len(multiprocessing.active_children())
 #czy liczba pod-procesow <= liczba mozliwych pod-
procesow
 if active_child <= self._deamon__liczba_proces:
 lista_zlecen = self._deamon__baza.get_work(

self.__liczba_wierszy(active_child))
 if len(lista_zlecen) > 0:
 for work_order in lista_zlecen:
 self.__info('start %s' %(work_order))
 pid =
self.__run_subprocess('typ1',work_order)
 self.__info('end %s %s' %(work_order,
str(pid)))
 time.sleep(self._deamon__sleep)
 elif active_child == self.__liczba_proces:
 msg = 'number of processes %i is equal to maximum
%i, '\
 'going sleep for %i seconds' %(
 active_child,
 self.__liczba_proces, self._deamon__sleep)
 self.__info(msg)
 time.sleep(self._deamon__sleep)
 else:
 self.__info('nothing to do... going sleep for %i
seconds'
 %(self._deamon__liczba_proces))
 #self._deamon__baza.zamknij_polacznie()
 time.sleep(self._deamon__sleep)
 except Exception, err:
 ei = sys.exc_info()
 msg = 'manager.run %s\n' %(str(err))
 sys.stderr.write('error in line %s\n' %
(str(ei[2].tb_lineno)))
 sys.stderr.write(msg)
 def receive_sygnal(self, signum, stack):
 if signum == 10:
 #print 'otrzymalem sygnal', signum
 self.__zapisz_status()
 elif signum == 12:
 self.__info('cheking if there are any active sub-
processes')
 while len(multiprocessing.active_children()) > 0:
 self.__info('liczba podprocesow > 0, ide spac na 10
sekund')
 time.sleep(10)
 else:
 print 'got unknown signal', signum