Database throttle

Overview:

Temporarily disables access to databases when CPU load is too high.
This module is most suitable for non-essential databases. Throttling the main database might cause the site not to be displayed correctly.

Requirements:

• Linux
• Memcache
• Crontabs

Features:

• You can tick the databases you want to throttle
• You can specify the CPU threshold for each database

Installation:

• Install the module
• Configure database server
• Install the probe script (cpu_probe.php) on /usr/local/bin/
• Change the host/port to suit your setup
• Configure a crontab to run the probe script. If you are not familiar with crontabs, you can have a look at
• this link http://kevin.vanzonneveld.net/techblog/article/schedule_tasks_on_linux_u...
• Crontab's minimum interval is one minute which sometimes can be too long until you take any action.
• If you need the script to be run in a shorter interval, you need to create a loop like it's suggested
• on this link http://www.linuxquestions.org/questions/programming-9/seting-cron-to-run...
• Configure any firewall rules that might be necessary to allow memcache to communicate to memcache on the web servers

Configuration:
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- Go to /admin/settings/db-throttle
- Tick the databases you want to enable throttle and set the threshold