&gt; I&#x27;m also using 4Kbit RSA keys, maybe that&#x27;s the cause, especially given that the server is a tiny Atom HTPC sitting in the kitchen<p>Yeah, the combination of those two things is very likely to not do you any favors.<p>It is worth clarifying that Google et al.&#x27;s claim that SSL is essentially no overhead is conditioned on the assumption that you&#x27;re using reasonably modern and full-featured processors, especially with AES-GCM in hardware. (Which is pretty common on laptop processors these days even without trying hard to find it, but probably won&#x27;t be on an Atom HTPC.) I think that&#x27;s reasonable, since if you&#x27;re seriously worried about performance and latency, you&#x27;re probably starting off with good hardware, and your worry is that investment will go to waste if you turn on SSL. At least for running a web server for fun on an old personal machine, the added latency is real and is unfortunate but I&#x27;d guess also not such a big deal. But maybe that&#x27;s a bad assumption?