pressflow

(moved from http://groups.drupal.org/node/148319)

our current web stack is an all IPv4, DIY implementation of,

    nginx
        multiple listeners on IPv4:80, IPv4:443
        proxypass to varnish-cache on 127.0.0.1:9000
      |
      |
    varnish-cache
        listener on 127.0.0.1:9000
        filter/pass to 'faux-CDN' on Apache2
            'img' -> 127.0.0.1:12003
            'css' -> 127.0.0.1:12002
            'js'  -> 127.0.0.1:12001
            '...' -> 127.0.0.1:12000
      |
      |
    apache2/mod_php,mod_deflate +
    Pressflow6/memcached(cache_inc/session_inc/lock_inc)
        listeners/vhosts on 127.0.0.1:1200{0,1,2,3}

our current web stack is an all IPv4, DIY implementation of,

	nginx
		multiple listeners on IPv4:80, IPv4:443
		proxypass to varnish-cache on 127.0.0.1:9000
	  |
	  |
	varnish-cache
		listener on 127.0.0.1:9000
		filter/pass to 'faux-CDN' on Apache2
			'img' -> 127.0.0.1:12003
			'css' -> 127.0.0.1:12002
			'js'  -> 127.0.0.1:12001
			'...' -> 127.0.0.1:12000
	  |
	  |
	apache2/mod_php,mod_deflate +
	Pressflow6/memcached(cache_inc/session_inc/lock_inc)
		listeners/vhosts on 127.0.0.1:1200{0,1,2,3}

all works as planned.

I've tried to go through the groups and forums to glean as much information as I could prior to posting this. I fall into the category of someone who is fairly familiar with drupal and mildly familiar with server setups. There is a wealth information on Performance and tuning, but it leaves the novice without a clear path of how to scale. I though I would post my setup here along with my confusion, in hopes that it will help other individuals in the same boat.

My Current Setup
I currently have 400K nodes and 100 users
I hope to be able to scale to 100k + users 5M Nodes

We’re running into an issue sending duplicate notifications to our users using the Notifications module on our Mercury Pressflow implementation. The duplicate messages are identical save one thing- the [node-url] token is being replaced with ‘default’ in one of the messages. All the other tokens in the message are being replaced correctly.
The duplicate emails do not happen consistently, maybe 10-15% of the notifications sent out, however a duplicate message always has the proper url & the ‘default’ url.

Hi everybody, I'm brand spanking new to the world of Pantheon and just set up my first Pantheon / Mercury site on slicehost thanks to Greg Coit's great writeup.

pressflow and varnish work best together with external caching turned on, correct?

but External caching mode skips boot and exit hooks.

However, path_alias_cache uses hook_exit to set the paths into cache.

Are these two modes incompatible?

i.e. does varnish caching with external preclude path alias caching?

If not, any ideas what I'm missing? If so, anyone have a workaround?

I am preparing to migrate a site with over 19 million nodes and a 2500 term taxonomy vocabulaty from Drupal 5 to 6. While reading up, I have discovered Pressflow and want to consider it. How do I proceed with the upgrade? Can I use the same strategy that I and others have used to migrate sites from Drupal 5 to 6, copying the database, then replacing the Drupal core files with Pressflow's core files? Or will that create a hopelessly broken site to pick up pieces for?

We're pleased to announce new AWS AMIs for Mercury 1.1 on Ubuntu Lucid. These Beta AMIs were made using the instructions posted here: http://groups.drupal.org/node/70268. AMI IDs after the jump...

Hi,

We begun our deployment of a large community website from a single machine that combined DB and web server two years ago. We experienced continuous growth and our system evolved significantly, different performance tunings led to the following setup (so far):

Hola gente!

Pues bien, habrán leído la noticia que Google va a utilizar para indexar sus sitios la velocidad de carga como un elemento más a medir. Si bien no es un elemento que va a pesar mucho en la determinación del PR (aparentemente menos del 1% del total de sitios se ha visto afectado hasta ahora), creo que es un tema de discusión interesante.