Let me add: I am paid to write books, not paid to ride herd on servers. Apache's what I know from days of yore; switching to a new platform means taking an opportunity cost hit.

Having said that, I'm looking at Varnish (once the stampede dies down) ...

If you add Varnish, you'll still need Apache.

If you switch to nginx, then you probably won't need varnish at all and can replace Apache.

The nginx config is much, much, much easier to work with than Apache. Transferring complex rewrite rules is the hardest thing to get right when moving over, but everything else is much easier.

Smart lobsters use nginx

I compared changing the Apache MPM, Varnish & nginx for a high-traffic, low memory (256M) server.

* Changing Apache would have required changing other packages - PHP wasn't thread-safe.

* Varnish looked fragile. I wish I still had my notes about why I thought that.

* Nginx in front of Apache was relatively quick to setup & really great in practice - restarting an order of magnitude less often.

If the nginx config file would be useful as a starting point, I offer it.

Edit: formatting.

Honestly - publish it on a blog somewhere or shove it into a github repo or whatever - but if it was useful to you, it's quite possibly useful to somebody else so you should publish by default rather than merely offering.

I'm not sure if it would help me, but I'm almost certain it would help other people - so please, consider your offer accepted if you can find somewhere easy to publish this :)

Why is varnish fragile? It is a bit odd to configure, but that seems like a set and forget kind of a thing.

The Varnish configuration is hairy - manually tweaking cookies to cache images for everybody while avoiding duplication, denormalizing headers so that IE & Firefox can both get the benefit of compression, dealing with pragma & cache-control, etc.

(Compression & other varying content was a headache - separately caching & serving gzip, deflate, & unpacked versions, without any built-in compression.)

Those tweaks looked time-consuming to set up, hard to test, & liable to break quietly. A buffer in the way that simply & quickly gets a response from (& then frees up) Apache, then slowly feeds the response to the client, provides most of the benefit; nginx fills this role well for me.

On one memory-constrained server, I have nginx reverse proxying to Apache, so the Apache-isms are not an immediate problem. I have nginx bypassing Apache for some static files. Having a ton of slow connections was a problem for Apache, but not for nginx.

Cherokee is actually pretty good at following .htaccess and mod_rewrite for the big blogging/cms engines (like drupal, wordpress). It is much easier to configure, though perhaps a bit more tedious, as it is all done through the web gui.

Other than that Apache is pretty much king with compatibility and nginx is pretty hard to get to similar qualities off the bat.

But if you have the space something like a reverse proxy for Apache with sane times set would probably be the better option.

I use cherokee on VPS's though and it works great.

I've moved almost exclusively to Nginx, once you get your head round how to do the "Apache-isms" (great potential neologism that :D) in Nginx configurations it becomes second nature.

Cherokee is a possible alternative too; that has some default configs for Wordpress etc. that work well. But for anything custom I found it a nightmare to get "just so".

Nginx is a neat alternative to Varnish as well; for example I'm having great success sitting it in front of a Cherokee site (serving the http) to provide SSL :)

Is varnish a drop in fix for something like this while everything is going to hell, or is there some monkeying that has to be done to make it play nice with movable type?

nothing really is a drop in solution for traffic spikes, however, there are a plethora of articles about how to make Varnish play nicely with moveable type:

http://www.coldhardcode.com/2009/04/varnish-and-movabletype-...

The same is true for wordpress:

http://www.varnish-cache.org/trac/wiki/VarnishAndWordpress