I have to admit I giggled

http://i.imgur.com/H9dBG09.png

Hope the rebuild goes well.

Redeploying is pretty automated, but it looks like I need significant caching on the front-end to cope with load.

I'm a huge fan of Varnish for this sort of thing.

Out of curiosity, what are the specs of the server, and how much RAM is "decent"?

Previously it was running a reasonably heavyweight Perl/CGI front-end on 512Mb RAM.

It's now setting with 4Gb of RAM, and a load of ~40.

The single biggest issue is that the front-page either shows "marketing" or "your details", so it is dynamic and being generated on-demand.

I'll update to cache.

Perl/CGI is never a good thing.

You might get better response with using perl in fastcgi mode, and using nginx rather than apache.

Why not just slap Varnish in front of that and be done?

That would be the end goal - but since all users get cookies there's not obvious "I'm anonymous" vs "I'm a signed-in-user" differentiator I can use to control whether to cache or serve live.

It'll happen, shortly, but the fastest solution was to re-deploy on a scaling platform.

When a user is logged in, use a Vary: Cookie header, when a user is not logged in, leave that off. Set the expiration time as appropriate.

Which brings the next question... why not use Github for authentication?