在这里仍然是一个学习者。我有一个Django网站，从一个月以来一直部署在Webpartition服务器上。
昨天，我尝试使用supervisor设置celery以在后台发送电子邮件。我刚完成设置，一切都正常了，突然我收到了来自Webpartition:的电子邮件
Hello,
Right now (2013-12-23 00:06:06 UTC) it appears that your processes on Web330 are using a lot more memory than your plan allows.
If you haven't read it yet, we recommend that you have a look at our "Reducing Memory Usage" article (http://docs.webfaction.com/software/general.html#reducing-memory-usage) for tips on how to keep your memory usage down.
Your total allowed memory is 512MB and your current memory usage is 1023MB.
Since your high memory usage is impacting other users on the server we had to kill your processes (our watchdog first sends a SIGTERM to your processes and then sends a SIGKILL a few seconds later).
You need to either find a way to keep your memory down or you'll have to upgrade to a plan that allows more memory.
Please respond to this message to let us know how you're dealing with the problem.
Below is the list of processes that you're running with the memory that they use (the command used to list these processes is "ps -u hammad -o rss,etime,pid,command"):
User - Memory - Elapsed Time - Pid - Command:
--------------------------------------------
/home/hammad/webapps/gccfishing/apache2/bin/httpd.worker -f /home/hammad/webapps/gccfishing/apache2/conf/httpd.conf -k start
hammad - 51MB - 0:16:44 - 428360 - /home/hammad/webapps/gccfishing/apache2/bin/httpd.worker -f /home/hammad/webapps/gccfishing/apache2/conf/httpd.conf -k start
hammad - 49MB - 0:16:44 - 428361 - /home/hammad/webapps/gccfishing/apache2/bin/httpd.worker -f /home/hammad/webapps/gccfishing/apache2/conf/httpd.conf -k start
hammad - 52MB - 0:16:44 - 428362 - /home/hammad/webapps/gccfishing/apache2/bin/httpd.worker -f /home/hammad/webapps/gccfishing/apache2/conf/httpd.conf -k start
hammad - 50MB - 0:16:44 - 428363 - /home/hammad/webapps/gccfishing/apache2/bin/httpd.worker -f /home/hammad/webapps/gccfishing/apache2/conf/httpd.conf -k start
hammad - 53MB - 0:16:44 - 428364 - /home/hammad/webapps/gccfishing/apache2/bin/httpd.worker -f /home/hammad/webapps/gccfishing/apache2/conf/httpd.conf -k start
hammad - 2MB - 0:16:44 - 428365 - /home/hammad/webapps/gccfishing/apache2/bin/httpd.worker -f /home/hammad/webapps/gccfishing/apache2/conf/httpd.conf -k start
hammad - 11MB - 0:06:29 - 435573 - /home/hammad/webapps/gccfishing/bin/python2.7 /home/hammad/webapps/gccfishing/bin/supervisord -c supervisord_prod.conf
hammad - 48MB - 0:06:28 - 435577 - /home/hammad/webapps/gccfishing/bin/python2.7 /home/hammad/webapps/gccfishing/bin/celery -A gccFishing worker -l info
hammad - 39MB - 0:06:27 - 435589 - /home/hammad/webapps/gccfishing/bin/python2.7 /home/hammad/webapps/gccfishing/bin/celery -A gccFishing worker -l info
hammad - 39MB - 0:06:27 - 435590 - /home/hammad/webapps/gccfishing/bin/python2.7 /home/hammad/webapps/gccfishing/bin/celery -A gccFishing worker -l info
hammad - 39MB - 0:06:27 - 435591 - /home/hammad/webapps/gccfishing/bin/python2.7 /home/hammad/webapps/gccfishing/bin/celery -A gccFishing worker -l info
hammad - 39MB - 0:06:27 - 435592 - /home/hammad/webapps/gccfishing/bin/python2.7 /home/hammad/webapps/gccfishing/bin/celery -A gccFishing worker -l info
hammad - 39MB - 0:06:27 - 435593 - /home/hammad/webapps/gccfishing/bin/python2.7 /home/hammad/webapps/gccfishing/bin/celery -A gccFishing worker -l info
hammad - 39MB - 0:06:27 - 435594 - /home/hammad/webapps/gccfishing/bin/python2.7 /home/hammad/webapps/gccfishing/bin/celery -A gccFishing worker -l info
hammad - 39MB - 0:06:27 - 435595 - /home/hammad/webapps/gccfishing/bin/python2.7 /home/hammad/webapps/gccfishing/bin/celery -A gccFishing worker -l info
hammad - 39MB - 0:06:27 - 435596 - /home/hammad/webapps/gccfishing/bin/python2.7 /home/hammad/webapps/gccfishing/bin/celery -A gccFishing worker -l info
hammad - 39MB - 0:06:27 - 435597 - /home/hammad/webapps/gccfishing/bin/python2.7 /home/hammad/webapps/gccfishing/bin/celery -A gccFishing worker -l info
hammad - 41MB - 0:06:27 - 435598 - /home/hammad/webapps/gccfishing/bin/python2.7 /home/hammad/webapps/gccfishing/bin/celery -A gccFishing worker -l info
hammad - 39MB - 0:06:27 - 435599 - /home/hammad/webapps/gccfishing/bin/python2.7 /home/hammad/webapps/gccfishing/bin/celery -A gccFishing worker -l info
hammad - 39MB - 0:06:27 - 435600 - /home/hammad/webapps/gccfishing/bin/python2.7 /home/hammad/webapps/gccfishing/bin/celery -A gccFishing worker -l info
hammad - 39MB - 0:06:27 - 435601 - /home/hammad/webapps/gccfishing/bin/python2.7 /home/hammad/webapps/gccfishing/bin/celery -A gccFishing worker -l info
hammad - 39MB - 0:06:27 - 435602 - /home/hammad/webapps/gccfishing/bin/python2.7 /home/hammad/webapps/gccfishing/bin/celery -A gccFishing worker -l info
hammad - 39MB - 0:06:27 - 435603 - /home/hammad/webapps/gccfishing/bin/python2.7 /home/hammad/webapps/gccfishing/bin/celery -A gccFishing worker -l info
hammad - 39MB - 0:06:27 - 435604 - /home/hammad/webapps/gccfishing/bin/python2.7 /home/hammad/webapps/gccfishing/bin/celery -A gccFishing worker -l info
hammad - 0MB - 52 days, 14:45:11 - 702447 -
Regards,
WebFaction team - http://www.webfaction.com
我想知道一些关于这方面的事情：
为什么有这么多Apache实例，这些内存用于什么？Apache不是只处理请求吗？如果是，那么每个实例的内存中都有什么？
为什么监管者催生了这么多芹菜实例？这是我的supervisord.conf文件：
[unix_http_server] file=/tmp/supervisor.sock ; (the path to the socket file) [supervisord] logfile=/tmp/supervisord.log ; (main log file;default $CWD/supervisord.log) logfile_maxbytes=50MB ; (max main logfile bytes b4 rotation;default 50MB) logfile_backups=10 ; (num of main logfile rotation backups;default 10) loglevel=info ; (log level;default info; others: debug,warn,trace) pidfile=/tmp/supervisord.pid ; (supervisord pidfile;default supervisord.pid) nodaemon=false ; (start in foreground if true;default false) minfds=1024 ; (min. avail startup file descriptors;default 1024) minprocs=200 ; (min. avail process descriptors;default 200) [supervisorctl] serverurl=unix:///tmp/supervisor.sock ; use a unix:// URL for a unix socket [program:celeryd] command=/home/hammad/webapps/gccfishing/bin/celery -A gccFishing worker -l info directory=/home/hammad/webapps/gccfishing/gccFishing/gccFishing numprocs=1 autostart=true autorestart=true startsecs = 10 stopwaitsecs = 900
再说一遍，每个Celery实例的内存是用来做什么的？我只是偶尔用它发送一些html(没有图像或图形)电子邮件给15-20个人。
它需要这么多内存吗？每次任务结束后，内存可以被清除吗？还是继续积累？
为什么有这么多Apache实例？同时回答请求。如果您的站点不需要每秒处理多次点击，那么您可能需要减少Apache工作人员的数量。您还可以移除未使用的模块，以进一步减少内存使用。
另一种可能性是用nginx代替Apache，用其他东西代替mod_wsgi，例如gunicorn。您可能需要在开发环境中检查应用程序的每个gunicorn进程的大小。Nginx本身非常轻量级，在我的一个生产服务器上，每个Nginx工作人员占用的空间不到3MB。
内存是用来做什么的？假设您使用mod_wsgi，它不仅用于Apache本身，也用于您的web应用程序。您可以使用像Heapy这样的Python堆探查器来深入了解单个内存的使用情况。通常，导入的每一位代码和创建的每一个对象都会占用内存。
celeryd worker的数量默认为可用CPU的数量，可以使用CELERYD_CONCURRENCY设置进行调整。工人们不是直接由监督员产生的，而是芹菜本身产生的。如果您不需要大量的吞吐量，您甚至可以将工作程序的数量减少到1或2，并节省相当多的内存。