Since you have a VirtualHost specific error log file, you also need to check the Apache wide error log file. This is because messages about process management are likely going to be in the Apache wide error log file.
Thus look for the ErrorLog directive which is outside of all VirtualHost blocks and then look it the log file it references. Graham On 14/10/2014, at 7:52 AM, Carlos Vicente <[email protected]> wrote: > Dear Graham, > > Thank you for your response. > > I can't see a Segmentation fault message (well at have grep(ed) for it). > Invariably, the log message I get is something like this: > > (...) > [Sat Oct 04 02:55:04 2014] [debug] src/server/mod_wsgi.c(7968): mod_wsgi > (pid=14256): Started thread 0 in daemon process 'ZigHomeWS'. > [Sat Oct 04 02:55:04 2014] [debug] src/server/mod_wsgi.c(7968): mod_wsgi > (pid=14256): Started thread 1 in daemon process 'ZigHomeWS'. > [Sat Oct 04 02:55:04 2014] [debug] src/server/mod_wsgi.c(7968): mod_wsgi > (pid=14256): Started thread 2 in daemon process 'ZigHomeWS'. > [Sat Oct 04 02:55:04 2014] [debug] src/server/mod_wsgi.c(7968): mod_wsgi > (pid=14256): Started thread 3 in daemon process 'ZigHomeWS'. > [Sat Oct 04 02:55:04 2014] [debug] src/server/mod_wsgi.c(7968): mod_wsgi > (pid=14256): Started thread 4 in daemon process 'ZigHomeWS'. > [Sat Oct 04 02:55:04 2014] [debug] src/server/mod_wsgi.c(7968): mod_wsgi > (pid=14256): Started thread 5 in daemon process 'ZigHomeWS'. > [Sat Oct 04 02:55:04 2014] [debug] src/server/mod_wsgi.c(7968): mod_wsgi > (pid=14256): Started thread 6 in daemon process 'ZigHomeWS'. > [Sat Oct 04 02:55:04 2014] [debug] src/server/mod_wsgi.c(7968): mod_wsgi > (pid=14256): Started thread 7 in daemon process 'ZigHomeWS'. > [Sat Oct 04 02:55:04 2014] [debug] src/server/mod_wsgi.c(7968): mod_wsgi > (pid=14256): Started thread 8 in daemon process 'ZigHomeWS'. > [Sat Oct 04 02:55:04 2014] [debug] src/server/mod_wsgi.c(7968): mod_wsgi > (pid=14256): Started thread 9 in daemon process 'ZigHomeWS'. > [Sat Oct 04 02:55:04 2014] [debug] src/server/mod_wsgi.c(7968): mod_wsgi > (pid=14256): Started thread 10 in daemon process 'ZigHomeWS'. > [Sat Oct 04 02:55:04 2014] [debug] src/server/mod_wsgi.c(7968): mod_wsgi > (pid=14256): Started thread 11 in daemon process 'ZigHomeWS'. > [Sat Oct 04 02:55:04 2014] [debug] src/server/mod_wsgi.c(7968): mod_wsgi > (pid=14256): Started thread 12 in daemon process 'ZigHomeWS'. > [Sat Oct 04 02:55:04 2014] [debug] src/server/mod_wsgi.c(7968): mod_wsgi > (pid=14256): Started thread 13 in daemon process 'ZigHomeWS'. > [Sat Oct 04 02:55:04 2014] [debug] src/server/mod_wsgi.c(7968): mod_wsgi > (pid=14256): Started thread 14 in daemon process 'ZigHomeWS'. > [Sat Oct 04 02:55:23 2014] [info] [client X.X.X.X] mod_wsgi (pid=14256, > process='ZigHomeWS', application=''): Loading WSGI script > '/usr/local/ZigHomeWS/zighome_rest/zighome_rest/WSGI/django.wsgi'. > [Sat Oct 04 02:55:25 2014] [error] [client X.X.X.X] Truncated or oversized > response headers received from daemon process 'ZigHomeWS': > /usr/local/ZigHomeWS/zighome_rest/zighome_rest/WSGI/django.wsgi > [Sat Oct 04 02:55:25 2014] [info] mod_wsgi (pid=14338): Attach interpreter ''. > [Sat Oct 04 02:55:25 2014] [info] mod_wsgi (pid=14338): Adding > '/usr/local/ZigHomeWS/zighome_rest' to path. > [Sat Oct 04 02:55:25 2014] [info] mod_wsgi (pid=14338): Adding > '/usr/lib/python2.7' to path. > [Sat Oct 04 02:55:25 2014] [info] mod_wsgi (pid=14338): Adding > '/usr/local/lib/python2.7/site-packages/django' to path. > [Sat Oct 04 02:55:25 2014] [info] mod_wsgi (pid=14338): Imported 'mod_wsgi'. > > [Sat Oct 04 02:55:25 2014] [debug] src/server/mod_wsgi.c(7968): mod_wsgi > (pid=14338): Started thread 0 in daemon process 'ZigHomeWS'. > [Sat Oct 04 02:55:25 2014] [debug] src/server/mod_wsgi.c(7968): mod_wsgi > (pid=14338): Started thread 1 in daemon process 'ZigHomeWS'. > [Sat Oct 04 02:55:25 2014] [debug] src/server/mod_wsgi.c(7968): mod_wsgi > (pid=14338): Started thread 2 in daemon process 'ZigHomeWS'. > [Sat Oct 04 02:55:25 2014] [debug] src/server/mod_wsgi.c(7968): mod_wsgi > (pid=14338): Started thread 3 in daemon process 'ZigHomeWS'. > [Sat Oct 04 02:55:25 2014] [debug] src/server/mod_wsgi.c(7968): mod_wsgi > (pid=14338): Started thread 4 in daemon process 'ZigHomeWS'. > [Sat Oct 04 02:55:25 2014] [debug] src/server/mod_wsgi.c(7968): mod_wsgi > (pid=14338): Started thread 5 in daemon process 'ZigHomeWS'. > [Sat Oct 04 02:55:25 2014] [debug] src/server/mod_wsgi.c(7968): mod_wsgi > (pid=14338): Started thread 6 in daemon process 'ZigHomeWS'. > [Sat Oct 04 02:55:25 2014] [debug] src/server/mod_wsgi.c(7968): mod_wsgi > (pid=14338): Started thread 7 in daemon process 'ZigHomeWS'. > > (...) > > I''ve also already attached the apache process to the gdb, but I only get > memory references... nothing I could use! > > As a matter of mitigating the problem and trying to find its source, I tried > to install the same architecture, but on nginx+uwsgi and its working fine. > Although I haven't quit on APACHE and mod_wsgi yet! > > It's rather change it only crashes when threads are launched from the SWIGed > software. > > Regards, > > Carlos > > On Sunday, October 12, 2014 7:01:15 AM UTC+1, Graham Dumpleton wrote: > Okay, this is your more recent update. > > On 06/10/2014, at 4:04 AM, Carlos Vicente <[email protected]> wrote: > >> I've a C++ application for which I needed to expose using a REST >> Web-Service. And for that purpose I am using started using DJANGO-REST. >> After successfully implemented and tested on the "DJANGO Development >> Server", I want to migrate it to Apache+MOD_WSGI. >> >> Up until now, every interface that implies, on the C++ part, to launch some >> threads, I get this message: >> >> [Sat Oct 04 02:55:25 2014] [error] [client X.X.X.X] Truncated or oversized >> response headers received from daemon process 'ZigHomeWS': >> /usr/local/ZigHomeWS/zighome_rest/zighom >> e_rest/WSGI/django.wsgi > > In mod_wsgi 4.3.0 the messages related to problems in reading back the > response from a mod_wsgi daemon process were changed. This was done so as to > distinguish a timeout in reading data from the mod_wsgi daemon and other > problems. > > This particular message above can occur for one of two reasons. > > The first is that the WSGI application returned a header which was larger > than the buffer being used to read each response header/value line returned > from the mod_wsgi daemon process. > > The second is if the daemon process crashed and there appeared to be > truncated or no headers returned from the mod_wsgi daemon process. > > In the event of the second, you would generally see a specific error message > in the Apache error log like 'Segmentation fault' indicating that the daemon > process crashed. > > Have a look for such a message around the point you see the above message. > > With a LogLevel of info or above (you have debug), you should also see > messages output from mod_wsgi about the daemon process vanishing and being > restarted if it crashed. So look for those messages as well. > > See what you find and send all the error messages emitted at about the time > the problem occurred. Depending on what you get, can then see which of the > two scenarios occurred. > > If it it the size of the headers, mod_wsgi 4.3.0 now has options for > WSGIDaemonProcess to allow the header buffer size when reading the response > headers to be overridden. > > If the daemon process is crashing, you need to attach gdb to the daemon > process as explained in: > > > http://code.google.com/p/modwsgi/wiki/DebuggingTechniques#Debugging_Crashes_With_GDB > > and try and work out where it is crashing. > > A random guess since you are using SWIG on something, and you are already > setting WSGIApplicationGroup to %{GLOBAL}, is that you are wrapping a shared > library that can't be found properly at runtime when the module is loaded and > that is causing a crash. > > Graham > >> (note that any other call, that implies calling other interfaces on the C++ >> part which does not involve thread launching, no problem occurs) >> >> At this point, and after upgrading some libraries just to make sure I wasn't >> working with some deprecated faulty version, I've: >> >> SWIG 3.0.2 >> MOD_WSGI 4.3.0 >> DJANGO (which ends up by being used by DJANGO-REST) 1.7 >> DJANGO-REST 2.3.13 >> Apache 2.2.2 >> >> I've followed the instructions described here >> https://code.google.com/p/modwsgi/wiki/ApplicationIssues, specially on the >> section "Python Simplified GIL state API", with no luck. >> >> Here is my configuration: >> >> Virtual host configuration: >> <VirtualHost *:80> >> ServerAdmin [email protected] >> ServerName my.server.com >> >> >> DocumentRoot /usr/local/DummyApp >> >> >> WSGIDaemonProcess ZigHomeWS >> python-path=/usr/local/ZigHomeWS/zighome_rest:/usr/lib/python2.7:/usr/local/lib/python2.7/site-packages/django >> WSGIProcessGroup ZigHomeWS >> WSGIApplicationGroup %{GLOBAL} >> >> >> WSGIScriptAlias /ZigHomeWS >> /usr/local/ZigHomeWS/zighome_rest/zighome_rest/WSGI/django.wsgi >> WSGIPassAuthorization On >> #WSGIPythonPath /usr/local/ZigHomeWS/zighome_rest >> >> >> >> >> <Directory /usr/local/ZigHomeWS/zighome_rest> >> Order allow,deny >> Allow from all >> </Directory> >> >> >> <Directory /usr/local/DummyApp> >> Order deny,allow >> Allow from all >> </Directory> >> >> >> ErrorLog /var/log/apache2/error_ZigHomeWS.log >> >> >> # Possible values include: debug, info, notice, warn, error, crit, >> # alert, emerg. >> LogLevel debug >> >> >> </VirtualHost> >> >> django.wsgi file: >> """ >> WSGI config for zighome_rest project. >> >> >> It exposes the WSGI callable as a module-level variable named >> ``application``. >> >> >> For more information on this file, see >> https://docs.djangoproject.com/en/1.6/howto/deployment/wsgi/ >> """ >> >> >> import os, sys >> sys.path.append('/usr/local/ZigHomeWS') >> sys.path.append('/usr/local/ZigHomeWS/zighome_rest') >> sys.path.append('/usr/local/lib/python2.7/site-packages/django') >> os.environ.setdefault("DJANGO_SETTINGS_MODULE", "zighome_rest.settings") >> >> >> from django.core.wsgi import get_wsgi_application >> application = get_wsgi_application() >> >> >> #import django.core.handlers.wsgi >> #application = django.core.handlers.wsgi.WSGIHandler() >> >> settings.py file: >> """ >> Django settings for zighome_rest project. >> >> >> For more information on this file, see >> https://docs.djangoproject.com/en/1.6/topics/settings/ >> >> >> For the full list of settings and their values, see >> https://docs.djangoproject.com/en/1.6/ref/settings/ >> """ >> >> >> # Build paths inside the project like this: os.path.join(BASE_DIR, ...) >> import os >> BASE_DIR = os.path.dirname(os.path.dirname(__file__)) >> >> >> >> >> # Quick-start development settings - unsuitable for production >> # See https://docs.djangoproject.com/en/1.6/howto/deployment/checklist/ >> >> >> # SECURITY WARNING: keep the secret key used in production secret! >> SECRET_KEY = '6h34&@m=1t4!(axkhz1+%6%u8^o(7^ao500pl#*+=$sk(a846@' >> >> >> # SECURITY WARNING: don't run with debug turned on in production! >> DEBUG = True >> >> >> TEMPLATE_DEBUG = True >> >> >> ALLOWED_HOSTS = [] >> >> >> >> >> # Application definition >> >> >> INSTALLED_APPS = ( >> 'django.contrib.admin', >> 'django.contrib.auth', >> 'django.contrib.contenttypes', >> 'django.contrib.sessions', >> 'django.contrib.messages', >> 'django.contrib.staticfiles', >> 'rest_framework', >> 'configuration', >> 'execution', >> ) >> >> >> MIDDLEWARE_CLASSES = ( >> 'django.contrib.sessions.middleware.SessionMiddleware', >> 'django.middleware.common.CommonMiddleware', >> 'django.middleware.csrf.CsrfViewMiddleware', >> 'django.contrib.auth.middleware.AuthenticationMiddleware', >> 'django.contrib.messages.middleware.MessageMiddleware', >> 'django.middleware.clickjacking.XFrameOptionsMiddleware', >> ) >> >> >> ROOT_URLCONF = 'zighome_rest.urls' >> >> >> WSGI_APPLICATION = 'zighome_rest.wsgi.application' >> >> >> >> >> # Database >> # https://docs.djangoproject.com/en/1.6/ref/settings/#databases >> >> >> DATABASES = { >> 'default': { >> 'ENGINE': 'django.db.backends.sqlite3', >> 'NAME': '/usr/local/ZigHomeWS/zighome_rest/zighome.db', >> 'USER': '', >> 'PASSWORD': '', >> 'HOST': '', >> 'PORT': '', >> } >> } >> >> >> # Internationalization >> # https://docs.djangoproject.com/en/1.6/topics/i18n/ >> >> >> LANGUAGE_CODE = 'en-us' >> >> >> TIME_ZONE = 'UTC' >> >> >> USE_I18N = True >> >> >> USE_L10N = True >> >> >> USE_TZ = True >> >> >> >> >> # Static files (CSS, JavaScript, Images) >> # https://docs.djangoproject.com/en/1.6/howto/static-files/ >> >> >> STATIC_URL = '/static/' >> >> >> directory structure under "/usr/local": >> ZigHomeWS/ >> zighome_rest >> config >> NodeSensors.xml >> NodeSensors.xsd >> Workflow.xml >> Workflow.xsd >> configuration >> admin.py >> admin.pyc >> configuration.vim >> __init__.py >> __init__.pyc >> migrations >> 0001_initial.py >> 0001_initial.pyc >> 0002_auto_20140914_1704.py >> 0002_auto_20140914_1704.pyc >> 0003_auto_20140919_1722.py >> 0003_auto_20140919_1722.pyc >> __init__.py >> __init__.pyc >> models.py >> models.pyc >> serializers.py >> serializers.pyc >> tests.py >> urls.py >> urls.pyc >> views.py >> views.pyc >> example.log >> execution >> admin.py >> admin.pyc >> Execution.vim >> __init__.py >> __init__.pyc >> models.py >> models.pyc >> tests.py >> urls.py >> urls.pyc >> views.py >> views.pyc >> log >> log.html >> manage.py >> teste.py >> zighome.db >> ZigHome.py >> ZigHome.pyc >> zighome_rest >> __init__.py >> __init__.pyc >> settings.py >> settings.pyc >> urls.py >> urls.pyc >> WSGI >> django.wsgi >> _ZigHome.so >> >> >> Any help would be greatly appreciated. >> >> Thank you! >> >> -- >> You received this message because you are subscribed to the Google Groups >> "modwsgi" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> To post to this group, send email to [email protected]. >> Visit this group at http://groups.google.com/group/modwsgi. >> For more options, visit https://groups.google.com/d/optout. > > > -- > You received this message because you are subscribed to the Google Groups > "modwsgi" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at http://groups.google.com/group/modwsgi. > For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "modwsgi" group. 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