python - "Can' t 开始一个新的线程错误”在 Python 中

Question

我正在运行一个脚本，它从 debian 软件包中提取信息并将其保存在数据库中。

从大约 100 个包中提取信息后发生错误。错误是“无法启动新线程” 为什么我会遇到这个错误？可能的解决方案是什么？

这是用来保存数据的代码:

for i in list_pack:

      if not i in oblist:        
        #Creating Packages
            slu=slugify(i)
            ob=Gbobject()
            ob.title=i
            ob.slug=slu
            ob.content=''
            ob.tags=tagname
        #with reversion.create_revision():
            ob.save()
            gb=Gbobject.objects.get(title=i)
            gb.objecttypes.add(Objecttype.objects.get(title='Packages'))
            gb.sites.add(Site.objects.get_current())
        #with reversion.create_revision():
            gb.save()
            gd=Gbobject.objects.get(title=i)
            print 'The Object created was',gd


            #Decsription
            try:
                atv=package_description_dict[i]
                atvalue=unicode(atv,'utf-8')
            except UnicodeDecodeError:
                pass
            try:
                lo=Gbobject.objects.get(title=i)
                loid=NID.objects.get(id=lo.id)
            except Gbobject.DoesNotExist:
                pass
            if atvalue<>'':
                slu=slugify(atvalue)
                at=Attribute()
                at.title=atvalue
                at.slug=slu
                at.svalue=atvalue
                at.subject=loid
                att=Attributetype.objects.get(title='Description')
                at.attributetype=att
                #with reversion.create_revision():
                at.save()                    
                print 'yeloow13'

就像 Description 一样，还有大约 !2 个以类似方式保存的包属性。

这是错误发生时我得到的完整回溯:-

    error                                     Traceback (most recent call last)

/home/radhika/Desktop/dev_75/gnowsys-studio/demo/<ipython console> in <module>()

/usr/local/lib/python2.6/dist-packages/django_gstudio-0.3.dev-py2.6.egg/gstudio/Harvest/debdata.py in <module>()
   1086 # create_attribute_type()

   1087 # create_relation_type()

-> 1088 create_objects()
   1089 #create_sec_objects()

   1090 #create_relations()


/usr/local/lib/python2.6/dist-packages/django_gstudio-0.3.dev-py2.6.egg/gstudio/Harvest/debdata.py in create_objects()
    403             ob.sites.add(Site.objects.get_current())
    404             #with reversion.create_revision():

--> 405             ob.save()
    406             #time.sleep(10)

    407             #gd=Gbobject.objects.get(title=i)


/usr/local/lib/python2.6/dist-packages/django_reversion-1.6.0-py2.6.egg/reversion/revisions.pyc in do_revision_context(*args, **kwargs)
    298             try:
    299                 try:
--> 300                     return func(*args, **kwargs)
    301                 except:
    302                     exception = True

/usr/local/lib/python2.6/dist-packages/django_gstudio-0.3.dev-py2.6.egg/objectapp/models.pyc in save(self, *args, **kwargs)
    658     @reversion.create_revision()
    659     def save(self, *args, **kwargs):
--> 660         super(Gbobject, self).save(*args, **kwargs) # Call the "real" save() method.
    661 
    662 

/usr/local/lib/python2.6/dist-packages/django_reversion-1.6.0-py2.6.egg/reversion/revisions.pyc in do_revision_context(*args, **kwargs)
    298             try:
    299                 try:
--> 300                     return func(*args, **kwargs)
    301                 except:
    302                     exception = True

/usr/local/lib/python2.6/dist-packages/django_gstudio-0.3.dev-py2.6.egg/gstudio/models.pyc in save(self, *args, **kwargs)
    327     @reversion.create_revision()
    328     def save(self, *args, **kwargs):
--> 329         super(Node, self).save(*args, **kwargs) # Call the "real" save() method.
    330 
    331 

/usr/local/lib/python2.6/dist-packages/django/db/models/base.pyc in save(self, force_insert, force_update, using)
    458         if force_insert and force_update:
    459             raise ValueError("Cannot force both insert and updating in model saving.")
--> 460         self.save_base(using=using, force_insert=force_insert, force_update=force_update)
    461 
    462     save.alters_data = True

/usr/local/lib/python2.6/dist-packages/django/db/models/base.pyc in save_base(self, raw, cls, origin, force_insert, force_update, using)
    568         if origin and not meta.auto_created:
    569             signals.post_save.send(sender=origin, instance=self,
--> 570                 created=(not record_exists), raw=raw, using=using)
    571 
    572 

/usr/local/lib/python2.6/dist-packages/django/dispatch/dispatcher.pyc in send(self, sender, **named)
    170 
    171         for receiver in self._live_receivers(_make_id(sender)):
--> 172             response = receiver(signal=self, sender=sender, **named)
    173             responses.append((receiver, response))
    174         return responses

/usr/local/lib/python2.6/dist-packages/django_gstudio-0.3.dev-py2.6.egg/objectapp/signals.pyc in wrapper(*args, **kwargs)
     65             if inspect.getmodulename(fr[1]) == 'loaddata':
     66                 return
---> 67         signal_handler(*args, **kwargs)
     68 
     69     return wrapper

/usr/local/lib/python2.6/dist-packages/django_gstudio-0.3.dev-py2.6.egg/objectapp/signals.pyc in ping_external_urls_handler(sender, **kwargs)
     90         from objectapp.ping import ExternalUrlsPinger
     91 
---> 92         ExternalUrlsPinger(gbobject)
     93 
     94 

/usr/local/lib/python2.6/dist-packages/django_gstudio-0.3.dev-py2.6.egg/objectapp/ping.pyc in __init__(self, gbobject, timeout, start_now)
    153         threading.Thread.__init__(self)
    154         if start_now:
--> 155             self.start()
    156 
    157     def run(self):

/usr/lib/python2.6/threading.pyc in start(self)
    472         _active_limbo_lock.release()
    473         try:
--> 474             _start_new_thread(self.__bootstrap, ())
    475         except Exception:
    476             with _active_limbo_lock:

error: can't start new thread

我没有编写任何代码来处理线程。

Answer 1

很抱歉这里有一个不完整的解决方案，我没有在评论部分发布的评级。

要检查的一件事是您正在运行的线程总数。我有一些代码检查核心数(使用 sys)，然后启动线程并检查核心加载以测试操作系统如何处理线程分配，我了解到 Windows 7(例如)似乎会抛出超过 32 个线程的错误在 8(逻辑)核心 CPU 上。 [这是在 Python 2.7 上，Win 7 64 位中的 32 位等，YMMMV]。在其他机器上，我可以超过 1,000 个线程。

所以我想简短的版本是:当您收到该错误时，您已经有多少个线程在运行？你可以检查

threading.active_count()

除此之外，您并没有真正在此处提供代码的线程部分，所以我会指导您查看这个优秀的 Python Central page .

您也可以从之前的 Stack overflow discussion 中受益关于大型线程任务计数以及如何处理它们。

再次抱歉，这更多的是寻找方向而不是解决方案，我认为可能需要更多信息来帮助我们了解您遇到的问题。