Nginx – Caching: Varnish vs fastcgi_cache on Nginx in a multiple websites envirnment

fastcginginxphp-fpmreverse-proxyvarnish

I have a setup of a VPS with several websites. Some of the websites are WP websites and some of them are other dynamic websites.

I'm interested in adding a sort of reverse proxy/caching layer. However I don't want to cache all the websites…

I've seen that a lot of people recommend using Varnish. The problem I found in Varnish is that it takes Port 80 and caches everything.

When I was looking for solutions, or ways to avoid cache for some websites, I found about fastcgi_cache. Apparently, you can cache directly through Nginx into files and then serve it statically. I've also seen somewhere that you can cache from Nginx into memcached, but I don't know how yet.

Anyway, here are my options:
1. Using Varnish and somehow tweaking the config files to pass requests based on Domain name.
2. Using fastcgi_cache on Nginx.
3. Using a sandwich. Having Nginx listening to port 80, serving the static files and sending all the php files to Varnish on another port which will pass all the uncached users to another Nginx instance.

What do you think that I should do?

Thanks.

Best Answer

You can have Varnish pass some requests through based on domain name, it's very easy and Varnish won't noticeably slow down the websites you aren't caching.

You just add a little VCL code in vcl_recv like:

if (req.http.Host == "www.pass_this_thru.com") {
    return(pass);
}

Related Solutions

Nginx – How to Set Up as a Caching Reverse Proxy

I don't think that there is a way to explicitly invalidate cached items, but here is an example of how to do the rest. Update: As mentioned by Piotr in another answer, there is a cache purge module that you can use. You can also force a refresh of a cached item using nginx's proxy_cache_bypass - see Cherian's answer for more information.

In this configuration, items that aren't cached will be retrieved from example.net and stored. The cached versions will be served up to future clients until they are no longer valid (60 minutes).

Your Cache-Control and Expires HTTP headers will be honored, so if you want to explicitly set an expiration date, you can do that by setting the correct headers in whatever you are proxying to.

There are lots of parameters that you can tune - see the nginx Proxy module documentation for more information about all of this including details on the meaning of the different settings/parameters: http://nginx.org/r/proxy_cache_path

http {
  proxy_cache_path  /var/www/cache levels=1:2 keys_zone=my-cache:8m max_size=1000m inactive=600m;
  proxy_temp_path /var/www/cache/tmp; 


  server {
    location / {
      proxy_pass http://example.net;
      proxy_cache my-cache;
      proxy_cache_valid  200 302  60m;
      proxy_cache_valid  404      1m;
    }
  }
}

Nginx & PHP caching: fastcgi_cache, proxy_cache, APC or memcached or combo

If your box can handle the entire cache on its own, memcache will only slow you down. APC is shared memory. Used right it will blow away memcached. Nginx fast cgi cache will make all dynamic php pages scream. Even if you set the cache to just 10 seconds, this makes it such that that max hit rate to any given php page will be once every 10 seconds. Makes it impossible to crash a page with load. I run a bunch of websites on a single small box that gets millions of people per month. All you need is nginx caching and APC at this point.

Memcache comes into the picture only when you have to scale your cache beyond a single box.

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