I doubt these spikes are caused by this plugin
It’s normal to see spikes in server resource usage. The level of resource use is dependent on a number of factors – here’s some of the common ones
1. Server processes for the site – e.g. cron runs (server cron and WordPress cron) produce spikes
2. Number of visitors to the site in a period of time – many visitors at the same time increase the use of resources. You can look at the “entry processes” to get an idea of concurrent active visits, compare to when you see a spike. Cpanel “Latest Visitors” also gives you an idea of site traffic
3. Bots – some bots hit the site at a high crawl rate – MSN (including Bing and Yahoo) bots especially – MSN bots may hit the site from 20 IPs at the same time and are heavy resource hogs. Keep an eye on “Latest Visitors” to monitor bot activity
4. Botnet attacks (DOS type attacks) – these may hit the site from 100s of IPs at the same time and can overload the server (which is what they are trying to do)
WP admin stuff and logged-in activity (subscribers etc) is also is more resource intensive than normal site traffic
You can reduce resource usage by caching the site – caching reduces the amount of resources used by reducing the need for the server to read the database for every page load. Further reduction in resource use can be achieved by minimising and combining CSS and JS files – each CSS and JS file adds to resource use – fewer means lower resources are needed.
Hope this info helps clarify things.
