Expose weave options

[dmac]

Weave accepts some options, such as the number of concurrent connections to use, that fezzik doesn't yet take advantage of. There are a few ways we could expose this:

1. Global option

   Fezzik.num_threads = 20

2. Option on host task

   host_task :foo, :num_threads => 20 do
   end

3. General exposure of weave options

   host_task :foo, :weave_options => {:num_threads => 20} do
   end

Other weave options to potentially add are :serial and :batch_by.

[dmac]

Weave options are now allowed on the same level as :deps, :args, and :roles, and are passed along to the weave connection pool.

[cespare]

Cool, I like this. The third option looks the messiest but I think it's the best because (a) it's not magical (there's no translation of certain options to weave options) and (b) you probably won't be specifying these options very often.

Side note: do you now get rolling deploys for free by doing :weave_options => { :batch_by => N, :num_threads => N } on your deploy host_task?

[dmac]

Almost. If you have the common setup of a single :deploy task that has many :host_tasks as dependencies, you couldn't (for example) add those options to the top level :deploy task.

You can, however, add them to your restart task, and you're basically good.

[cespare]

Oh, will those settings not recursively apply? It seems like they should.

[dmac]

I meant that you can't specify them on task, just host_task.