How to make 1000 requests in Scala and add up the total result?

Question

Scala

I'm in Skala for a couple of days. After the docks, there was a misunderstanding.
There is, for example, a url, user/info/:id, which produces homogeneous data.
I need to send 1000 requests like: user/info/1, user/info/2, user/info/1000
and merge the result together.
Consistently - too slow.
I did this:
====

val u1 = Future {
            ..... do request
    }

    val u1000 = Future {
            ..... do request
    }

    val req = Future.sequence(Seq(u1, u2, u1000))
    var result = Await.result(req, duration)

1. Future.sequence(Seq(u1, u2, u1000)) Does the Future run in parallel or sequentially? If in parallel, how many threads?
2. Do I understand correctly that Await.result(req, duration) does blocking until all Futures are completed.
3. How to speed up the code?

Answer 1

Good afternoon)
In this form, any decision will be a crutch. It's best to use the Akka Streams paradigm.
i) Create a Source that will contain all possible requests
ii) Create a Flow that will send requests in parallel. You can use Map, you can specify the number of threads there.
iii) Create a Sink that will accumulate responses.
iv) At the output, get one Future with all the answers.
v) Profit) More details here .

Answer 2

1) sequence will not start future execution. Futures start executing at the moment of creation, i.e. even before sequence.
2) Correct. Only you also have a timeout. Doing so is not very good. Use onComplete/map
3) You'd better look at ParSeq for this task.