Experienced in PHP but new to Drupal so please be gentle with me.
Very small Drupal site, hosted on my own beefy Linux server, and everything seems to work swimmingly. That is ... until I get lengthy (15-20 seconds) and seemingly random delays on clicking a link which would normally respond almost instantly.
I don't think it is network-related; I have 20Mbit service from Zen and this is solid as a rock.
The watchdog table has some entries for "Attempting to re-run cron while it is already running" ... dozens rather than thousands though.
Any pointers greatly appreciated,