I'm testing the limit of my Python Flask web application running on an Apache web server by making a request that takes over 30minutes to complete. The request requires thousands of database requests (one after the other) to a MySQL database. I understand this should ideally be run as a separate asynchronous process outside the apache server, but let's ignore that for now. The problem I'm having is that although this runs completely when I test it on my mac, it dies abruptly when running it on a linux server (Amazon linux on AWS EC2). I've not been able to figure out exactly what's killing it. I've checked that the server isn't running out of memory. The process uses very little RAM. I've not been able to find any Apache config parameter or any error message that makes sense to me (even after setting apache logLevel to debug). Please I need help on where to look. Here're more details about my setup:
Run Time
Server: It died after 8mins, 27mins, 21mins & 22mins respectively. Note that most of these runs were on a UAT server and this was the only request the server was processing.
Mac: It ran much slower that it runs on the server. The process ran successfully and took 2hours 47mins.
Linux Server details:
2 virtual CPUs and 4GB RAM
OS (output of uname -a)
Linux ip-172-31-63-211 3.14.44-32.39.amzn1.x86_64 #1 SMP Thu Jun 11 20:33:38 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux
Apache error_log: https://drive.google.com/file/d/0B3XXZfJyzJYsNkFDU3hJekRRUlU/view?usp=sharing
Apache config file: https://drive.google.com/file/d/0B3XXZfJyzJYsM2lhSmxfVVRNNjQ/view?usp=sharing
Apache version (output of apachectl -V)
Server version: Apache/2.4.23 (Amazon)
Server built: Jul 29 2016 21:42:17
Server's Module Magic Number: 20120211:61
Server loaded: APR 1.5.1, APR-UTIL 1.4.1
Compiled using: APR 1.5.1, APR-UTIL 1.4.1
Architecture: 64-bit
Server MPM: prefork
threaded: no
forked: yes (variable process count)
Server compiled with....
-D APR_HAS_SENDFILE
-D APR_HAS_MMAP
-D APR_HAVE_IPV6 (IPv4-mapped addresses enabled)
-D APR_USE_SYSVSEM_SERIALIZE
-D APR_USE_PTHREAD_SERIALIZE
-D SINGLE_LISTEN_UNSERIALIZED_ACCEPT
-D APR_HAS_OTHER_CHILD
-D AP_HAVE_RELIABLE_PIPED_LOGS
-D DYNAMIC_MODULE_LIMIT=256
-D HTTPD_ROOT="/etc/httpd"
-D SUEXEC_BIN="/usr/sbin/suexec"
-D DEFAULT_PIDLOG="/var/run/httpd/httpd.pid"
-D DEFAULT_SCOREBOARD="logs/apache_runtime_status"
-D DEFAULT_ERRORLOG="logs/error_log"
-D AP_TYPES_CONFIG_FILE="conf/mime.types"
-D SERVER_CONFIG_FILE="conf/httpd.conf"
Mac details:
Apache config file: https://drive.google.com/file/d/0B3XXZfJyzJYsRUd6NW5NY3lON1U/view?usp=sharing
Apache version (output of apachectl -V)
Server version: Apache/2.4.18 (Unix)
Server built: Feb 20 2016 20:03:19
Server's Module Magic Number: 20120211:52
Server loaded: APR 1.4.8, APR-UTIL 1.5.2
Compiled using: APR 1.4.8, APR-UTIL 1.5.2
Architecture: 64-bit
Server MPM: prefork
threaded: no
forked: yes (variable process count)
Server compiled with....
-D APR_HAS_SENDFILE
-D APR_HAS_MMAP
-D APR_HAVE_IPV6 (IPv4-mapped addresses enabled)
-D APR_USE_FLOCK_SERIALIZE
-D APR_USE_PTHREAD_SERIALIZE
-D SINGLE_LISTEN_UNSERIALIZED_ACCEPT
-D APR_HAS_OTHER_CHILD
-D AP_HAVE_RELIABLE_PIPED_LOGS
-D DYNAMIC_MODULE_LIMIT=256
-D HTTPD_ROOT="/usr"
-D SUEXEC_BIN="/usr/bin/suexec"
-D DEFAULT_PIDLOG="/private/var/run/httpd.pid"
-D DEFAULT_SCOREBOARD="logs/apache_runtime_status"
-D DEFAULT_ERRORLOG="logs/error_log"
-D AP_TYPES_CONFIG_FILE="/private/etc/apache2/mime.types"
-D SERVER_CONFIG_FILE="/private/etc/apache2/httpd.conf"
