Rails 4 Puma concurrency with Capistrano

Question

I am trying to deploy a concurrent Rails 4 Puma app with capistrano and was confused by the example of capistrano-puma gem.

From the snipper from github

set :puma_threads, [0, 16]
set :puma_workers, 0

1. What are the differences of threads and workers in puma?
2. What does 0 puma worker means and [0, 16] threads mean?
3. What are the parameters to achieve concurrency? My aim is to achieve simple SSE to send notification. What are the best parameters to do in puma?

I am sorry if these are simple questions but i am having hard time finding resources online even on the official site, if someone can point me to an article which answer my question, i am happy to accept it. Thanks.

Answer 1

在任何文档中都找不到，我想设置了：puma_workers，0表示无限的puma工人。

Answer 2

A worker is the number of processes running or instances of your application. Each instance can run multiple threads. So if you have 2 workers running with max 16 threads it means your server can serve 2 * 16 = 32 requests at a time and if avg response time of your request is 100ms it means per second requests that could serve = (1000/100) * 32 = 320rps approx.