async-http-client | HTTP client library built on SwiftNIO | Web Framework library

Future#sequence should execute the HTTP requests in parallel?

First of all, Future#sequence doesn't execute anything. It just produces a future that completes when all parameters complete. Evaluation (execution) of constructed futures starts immediately If there is a free thread in the EC. Otherwise, it simply submits it for a sort of queue. I am sure that in the first case you have single thread execution of futures.

println(scala.concurrent.ExecutionContext.Implicits.global) -> parallelism = 6

Don't know why it is like this, it might that other 5 thread is always busy for some reason. You can experiment with explicitly created new EC with 5-10 threads.

The difference with the Async case that you don't create a future by yourself, it is provided by the library, that internally don't block the thread. It starts the async process, "subscribes" for a result, and returns the future, which completes when the result will come.

Actually, async lib could have another EC internally, but I doubt.

Btw, Futures are not supposed to contain slow/io/blocking evaluations without blocking. Otherwise, you potentially will block the main thread pool (EC) and your app will be completely frozen.

If you are using IntelliJ it is worth checking which Gradle are you using for given project (can be wrapper, task, local). To do so go to Settings and search for Gradle. Then navigate to Build,Execution,Deployment -> Build Tools -> Gradle

They're orthogonal concepts, so that's why you don't see them mentioned in the same answers.

The aim of AsyncHttpClient is (among other things) to use a single thread for all network communication (performed internally by Netty through Java's NIO in a non-blocking asynchronous way), instead of the traditional thread-per-request model. On top of the network layer's single thread, the library has worker threads that perform the application level asynchronous handling visible to the users of AsyncHttpClient, meaning it already has a (small) internal pool of threads.

ForkJoinPool strives to maximize CPU usage by having many threads (the common pool has by default CPU cores - 1, ones you create can have more/less) and through work stealing so the threads aren't idle, and this is most efficient with small recursive tasks.

The link discusses that work stealing is also efficient with non-recursive tasks. The word "async" threw you off there, but it's just referring to a regular task that you submit to a pool, and it finishes asynchronously.

So you can either do thread-per-request (i.e. Basic I/O, or "old I/O") with a thread-pool, or you can use single threaded non-blocking NIO (i.e. New I/O) without a thread-pool.

Combining them doesn't make sense. You would migrate from a thread-per-request model to a non-blocking model to improve performance.

Trying add bellow dependency which included logback-classic

I’m afraid that at the moment you do need to make a new request from your delegate. Currently there is no way to automatically send a new request.

It is because the main thread is getting executed before the request is done so no print statement will get called unless you ask the main thread to wait for the httpclient

https://github.com/swift-server/async-http-client/issues/129

You have a number of problems going on. As you said, you are using jenkins:2.190.2 but your plugins list is from: jenkins:1.647 (2016/02/04). A lot has changed, not just in the major bump, but in each LTS as well and in the plugins.

docker/plugins.sh has been superseded by docker/install-plugins.sh. Usage here.

echo "WARN: plugins.sh is deprecated, please switch to install-plugins.sh"

install-plugins.sh will resolve and download all dependencies for your plugins (each plugin list lists them in the details on the site), so your managed list can be much shorter. Just list the top-level plugins you need and it will resolve all dependencies. Maven plugins have progressively dropped unused dependencies as well.

NB: if you want a known configuration (not latest), run once with the master list using latest, then check-in that and the resolved list. Feed the resolved list to docker instance.

You can use this script to simplify your list:

The error is no such column: newsblock0_.id. Clearly it says in the news_block block table, there is no id which means, spring-boot considered the id in your Entity class since you declare it. Entity class is more or less equal to your table.

It expects all variable that you declare must be in the table, But sometimes you declare a variable which is no need to be in the table. So you should denote @Transient.

@Transient annotation is used to indicate that a field is not to be persisted in the database.

AHC has two types of threads:

1. For I/O operation. On your screen, it's AsyncHttpClient-x-x threads. AHC creates 2*core_number of those.
2. For timeouts. On your screen, it's AsyncHttpClient-timer-1-1 thread. Should be only one.

Any different number means you’re creating multiple clients.

Source: issue on GitHub https://github.com/AsyncHttpClient/async-http-client/issues/1658