W3 Total Cache – Use persistent connections

‘persistent connections’ is something that needs to be done at the server configuration level. It may be possible with an .htaccess edit. I’m not sure. I go straight to the server config files when I can.

If you are using Apache, what that message refers to is the ‘KeepAlive’ directive, but don’t switch that on blindly despite the insistence of webpagetest.org (which I like very much)– https://abdussamad.com/archives/169-Apache-optimization:-KeepAlive-On-or-Off.html