wp_posts most time consuming

Hi,

Everyday when the traffic increases (around 6pm and 11pm) I start receiving several alerts from my PHP Application on New Relic of low apdex score, high throughput despite server CPU and memory are normal.

I am investigating it and this problem seems to be somehow related to wp_posts select as it is by far the most time consuming table as you can see here https://db.tt/zWmBD7Gf

Is it possible that this problem is related to your plugin?

Thanks

https://wordpress.org/plugins/subscribe-to-comments-reloaded/