This would be a page view every 5 seconds.
I can't image how you'd write a web server that couldn't cope with that low load (actually I can but not for a mostly static site like this).
Even if we consider that it would be an additional page view every 5 seconds, this is barely believable that this would put the server under a stress load.
Either this one is wildly more popular or maybe something else is going on as well.
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