Apache/performance

Get Stats

To get statistics, you'll need to potentially modify your Apache configuration. For Ubuntu, it's as easy as a2enmod status (and reload the server with service apache2 reload)

Cli

# Using wget isn't advised because you'll get html output.  However, if you simply append the ?auto querystring, you'll get machine readable output.
wget http://localhost/server-status -O -
curl localhost/server-status?auto
# Ubuntu
apache2ctl fullstatus
# Older/RedHat
apachectl fullstatus

Or you can edit /mods.enabled/status to get it from the browser. For a machine readable, condensed version, just append the auto querystring argument:

e.g. http://example.com/server-status?auto

Killing Stuck Processes

This script from Alain Kelder shows how you can identify and kill long-running processes without restarting Apache. I ran into this problem with a misbehaving Mantis plugin.

#/bin/bash

GetAllWorkers()
{
 AllWorkers=$(apache2ctl fullstatus | awk '/^Srv /,/^$/ {print}')
}

GetStuckWorkers()
{
 StuckWorkers=$(echo "$AllWorkers" | awk '$4 == "W" && $6 > 60 && $7 == 0 && $8 == "0.0" {print}')
 header=$(echo "$AllWorkers" | head -n 1)
}

GetStuckPIDs()
{
 StuckPIDs=$(echo "$AllWorkers" | awk '$4 == "W" && $6 > 60 && $7 == 0 && $8 == "0.0" {print$2}')
}

Show()
{
 echo "--------------------------------"
 echo " Stopped on $(date +%F\ %T)"
 echo "--------------------------------"
 echo "$header"
 echo "$StuckWorkers"
}

GetAllWorkers && GetStuckPIDs
if [ -n "$StuckPIDs" ]; then
  for PID in $StuckPIDs; do
    echo stopping $PID with SIGTERM
    kill $PID
  done
  GetStuckWorkers
  Show | mail -s "$(basename $0) executed on $(hostname -s)" root
  Show >> /path/to/ksaw.log
fi

Resources

1. https://httpd.apache.org/docs/2.4/misc/perf-tuning.html
2. https://www.linode.com/docs/websites/apache-tips-and-tricks/tuning-your-apache-server