Re: multithreading not working for requests to the same url

[Konstantin Haase <k.haase@finn.de>]

Concurrency is up to the concrete Rack handler (webserver), not rack.

Konstantin

On Jan 21, 2011, at 13:47 , Mathijs wrote:

> Hi all,
> 
> 
> In my application, a lot of time is spent on /inbox.
> However, it looks as if rack does not support handling multiple
> requests to the same url simultaneously.
> 
> I used this 'demo' app:
> class HelloWorld
>  def call(env)
>    sleep 15
>    [200, {'Content-Type' => 'text/plain'}, ["Hello world!"]]
>  end
> end
> run Helloworld.new
> 
> run with rackup demo.ru
> open 3 browser tabs, enter these urls:
> - http://localhost:9292/path1
> - http://localhost:9292/path1
> - http://localhost:9292/path2
> 
> You'll see that if you start the requests roughly at the same time,
> the first path1 and path2 will complete at the same time.
> The second path1 comes 15sec behind.
> 
> Passing params (localhost:9292/path1?blah=3) will
> trick the app to handle the request in parallel. Also, aliasing
> localhost does the trick.
> So it looks as if rack does some locking per url.
> I couldn't find anything though.
> 
> I tried this under REE with mongrel and webrick and under jruby with
> trinidad and webrick.
> They all behave the same.
> 
> Is anyone aware of this behavior? What is the cause?
> Thanks,
> Mathijs