I'm a bit hazy on how to switch from prefork MPM to worker MPM. Since results from Paul's apache2 -V command seem to show his apache server was compilted with the prefork option, does this indicate a recompilation to include worker.c?
On Aug 13, 5:56 am, Graham Dumpleton <graham.dumple...@gmail.com> wrote: > You should be able to get list of modules actually being load by using > the -M command to Apache. Thus: > > apache2 -M > > Now. I am going to go through things to try as a series of emails over > time as don't have state of mind now to try and do it all at once. > > First up. If not using PHP then disable mod_php. > > Second, now that you have got rid of mod_php, switch Apache > installation from prefork MPM to worker MPM. > > Third, since you are using mod_wsgi daemon mode, ensure that mod_wsgi > doesn't unnecessarily enable Python interpreters in Apache child > processes. For that read: > > http://blog.dscpl.com.au/2009/11/save-on-memory-with-modwsgi-30.html > > Changing from prefork to worker MPM and ensuring the Python > interpreters aren't initialised when not needed, will cut down on > memory footprint in the Apache child processes which do the proxying > to mod_wsgi daemon mode processes. This is because instead of > potentially up to 150 processes under excessive load, you would at > most have 6 processes. You have so few now because each of those 6 can > handle 25 concurrent requests in worker MPM where as prefork needed a > separate process for each request. > > To try and gauge progress on this before you start, change: > > WSGIDaemonProcess site-1 user=my-user group=www-data threads=25 > > to: > > WSGIDaemonProcess site-1 user=my-user group=www-data threads=25 > display-name=%{GROUP} > > When you do a 'ps' now, the mod_wsgi daemon processes will be named > '(wsgi:site-1)' and can be distinguished easily from Apache root and > child process. > > Use 'ps' to look at number of processes and sizes before making the > other changes above. For example, on my Mac OS X box with prefork I > see: > > $ ps auxwwww | egrep 'httpd|USER' | grep -v grep > USER PID %CPU %MEM VSZ RSS TT STAT STARTED TIME COMMAND > _www 58942 0.0 0.1 2440732 2184 ?? S 7:31am 0:08.82 > /usr/sbin/httpd -D FOREGROUND > _www 58941 0.0 0.1 2440732 2184 ?? S 7:31am 0:08.83 > /usr/sbin/httpd -D FOREGROUND > _www 58940 0.0 0.1 2440732 2196 ?? S 7:31am 0:08.79 > /usr/sbin/httpd -D FOREGROUND > _www 58937 0.0 0.1 2440732 2184 ?? S 7:30am 0:08.82 > /usr/sbin/httpd -D FOREGROUND > root 58908 0.0 0.0 2439768 1208 ?? Ss 7:30am 0:01.97 > /usr/sbin/httpd -D FOREGROUND > _www 61069 0.0 0.1 2440732 2232 ?? S 11:22am 0:05.44 > /usr/sbin/httpd -D FOREGROUND > _www 60310 0.0 0.1 2440732 2184 ?? S 9:47am 0:06.62 > /usr/sbin/httpd -D FOREGROUND > > You would grep for 'apache2' and not 'httpd'. > > The 'root' owned process is the Apache parent process and the rest are > the Apache child processes proxying to the mod_wsgi daemon processes > and which would also be handling static file handling if Apache being > used for that. > > Remember to check this when traffic flowing and now just when idle as > Apache will dynamically create more and more processes to meet demand. > You can read a bit about that at: > > http://blog.dscpl.com.au/2009/03/load-spikes-and-excessive-memory-usa... > > So, disable PHP, switch to worker MPM and disable interpreter > initialisation in embedded mode and restrict code execution in > embedded mode just to catch and configuration stuff ups. > > Then capture 'ps' output and post both so can compare. > > BTW, out of the modules you are loading into Apache, if you can say > which you think you are using. I note for example that rpaf is being > loaded. Are you actually using that? > > After we look at results for changes above, then we can look at what > is the minimum set of Apache modules you need and strip those back. > > Graham > > On 13 August 2011 05:21, Paul Walsh <paulywa...@gmail.com> wrote: > > > > > > > > > Oh, ok, to check MPM on Ubuntu was as simple as apache2 -V. > > That shows me: > > Server MPM: Prefork > > threaded: no > > forked: yes (variable process count) > > Server compiled with.... > > -D APACHE_MPM_DIR="server/mpm/prefork" > > -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=128 > > -D HTTPD_ROOT="/etc/apache2" > > -D SUEXEC_BIN="/usr/lib/apache2/suexec" > > -D DEFAULT_PIDLOG="/var/run/apache2.pid" > > -D DEFAULT_SCOREBOARD="logs/apache_runtime_status" > > -D DEFAULT_LOCKFILE="/var/run/apache2/accept.lock" > > -D DEFAULT_ERRORLOG="logs/error_log" > > -D AP_TYPES_CONFIG_FILE="mime.types" > > -D SERVER_CONFIG_FILE="apache2.conf" > > > -- > > You received this message because you are subscribed to the Google Groups > > "modwsgi" group. > > To view this discussion on the web visit > >https://groups.google.com/d/msg/modwsgi/-/_jUgBgryjacJ. > > To post to this group, send email to modwsgi@googlegroups.com. > > To unsubscribe from this group, send email to > > modwsgi+unsubscr...@googlegroups.com. > > For more options, visit this group at > >http://groups.google.com/group/modwsgi?hl=en. -- You received this message because you are subscribed to the Google Groups "modwsgi" group. 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