This is a long shot. I know, so please bear with me.

I have some 6-7 linodes, smaller ones, from when they were called other things than 1GB, 2GB etc. All running like clockwork.
All pretty much setup in the same way. LEMP stack on Debian. The only thing differing between them is the version of Debian and Nginx, MySql, PHP.

With this new Linode that I got, an 8GB, I've set it up just like I set up the others - a LEMP installation on Debian 7.6 - but here I get this weird problem.

I only run one site on it and it works really good except from time to time - maybe once per hour - it hangs for 2-3 seconds when rendering a page.
I've tried to look into the problem and concluded that it's not MySQL i.e. it's not a query that all of a sudden hangs or is not using index etc.

As I said, it's a fairly unspecific issue and I get that it's a long shot writing about it here but I still wanted to bring this forward in case someone else has had similar problems, just to hear what you did to solve them.

Since this hasn't happened on my other linodes, I also started thinking about what differs between this one and the other linodes and the only thing I can think of is that this new linode has SSD and of course newer versions of Nginx, PHP and also Debian (i.e. the OS itself).

So, anyone who's had similar issues?

Thanks.

Have you ruled out external resources on the page that's stalling (e.g. CSS, JS, images)? See if you can reproduce it using curl or wget.

A slow DNS lookup is another possibility. Check your TTLs.

You know what, I think you just hit the nail on the head with that one.
I'm doing a "gethostbyaddr" call on the page where this happens and I sure feel stupid not having thought about that as being the culprit.

Thanks still for making me find it.

Happens to the best of us. In the wise words of Kris Buytaert, "Everything is a Freaking DNS problem"