Varnish in Five Acts

http://dev.theladders.com/2013/05/varnish-in-five-acts/

by spooneybarger • 13 years ago

41 23 13 years ago

dev.theladders.com

j72• 13 years ago

Varnish is pretty awesome, but gets complicated when you have user-specific content. You can use things like edge-side includes and such, but it becomes more than plug and play at that point.

spooneybarger6• 13 years ago

to make sure I understand, you meant it becomes more plug and play when you use ESI?

IbJacked• 13 years ago

I believe he is saying it becomes less plug and play. By saying "it becomes more than plug and play at that point," he means it becomes more effort than plug and play.

That's my read on it, anyway. It always gets dicey interpreting the intent of others :)

robmil3• 13 years ago

For a lot of sites, either using ESIs or including dynamic content via AJAX is a fairly simple solution that still leaves you with the benefits of caching.

megaman821• 13 years ago

For light page customizability like Hello Username. I will include the username in a browser cookie and use some JavaScript to insert it into the page. This way I can still use Varnish to serve most pages.

jconnolly2• 13 years ago

what's up with the /donjohnson/pulse url?

fallous• 13 years ago

A reference to Don Johnson's terrible "Hearbeat" song from the 80s?

spooneybarger6• 13 years ago

indeed... https://www.youtube.com/watch?v=ULI5kolBpAk

mattwalker• 13 years ago

Has anyone found a decent Varnish plugin for Sublime Text/Textmate? There's this -- https://github.com/zephirworks/Varnish.tmbundle -- but it hasn't been updated in a couple years and it fails for moderately complex configs.

The Python plugin works reasonably well for plain VCL syntax highlighting.

jconnolly2• 13 years ago

need to write me some pygments-vcl for vcl syntax highlighting in octopress and elsewhere.

robmil3• 13 years ago

We eventually abandoned Varnish because the purging was too far from our application logic. nginx serves static content just as fast as Varnish does, and so getting our application to write static HTML files that were redirected to via nginx was just as quick as Varnish but easier to purge when needed.

evantahler• 13 years ago

This is what we did at TaskRabbit, and here's our rails midleware to do it: https://github.com/taskrabbit/storehouse

robmil3• 13 years ago

We started off with our own toolkit for purging domains after deploys: https://github.com/robmiller/Varnish-Toolkit

But yeah, it just got a bit painful after a while.

jjoergensen2• 13 years ago

I do not think that he should overwrite vcl_hash. By default Varnish caches by the request host and not the backend host?

Here is the default:

sub vcl_hash { hash_data(req.url); if (req.http.host) { hash_data(req.http.host); } else { hash_data(server.ip); } return (hash); }

spooneybarger6• 13 years ago

it caches by host. this would allow you to serve multiple sites through it like:

example.com/foo

and

another.com/foo

without a cache collision.

we don't care about the host as everything is of the same entity service type.

jjoergensen2• 13 years ago

I must have scanned the blog post too quickly. Thanks for the clarification.

lucid83• 13 years ago

What did you use to generate those graphs? Love 'em, have to know.

spooneybarger6• 13 years ago

Graphite

KevBurnsJr2• 13 years ago

Statsd is awesome. http://codeascraft.etsy.com/2011/02/15/measure-anything-meas...

KevBurnsJr2• 13 years ago

It's nice to see x-invalidates in the wild!

Do you have just 1 varnish instance or two?

I never did fully solve the ban propagation problem when running multiple redundant varnish instances.

spooneybarger6• 13 years ago

1 for each service. If we need to scale beyond one per service, I plan on doing sharing across varnishes based on url so we don't have to propagate bans.

Varnish in Five Acts

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