Concurrency
===========

This document describes the concurrency considerations for http/2 connections and the connection pool within OkHttp.

## HTTP/2 Connections

The HttpURLConnection API is a blocking API. You make a blocking write to send a request, and a blocking read to receive the response.

#### Blocking APIs

			// the concurrency make sure we choose only the "start"
			// concurrency to be equal to the lowest number of
			// local disks per server.
			for _, localDiskCount := range globalEndpoints.NLocalDisksPathsPerPool() {
				if localDiskCount < concurrency {
					concurrency = localDiskCount
				}
			}

			// Any concurrency less than '4' just stick to '4' concurrent
			// operations for now to begin with.

### Concurrency and Burgers { #concurrency-and-burgers }

This idea of **asynchronous** code described above is also sometimes called **"concurrency"**. It is different from **"parallelism"**.

**Concurrency** and **parallelism** both relate to "different things happening more or less at the same time".

But the details between *concurrency* and *parallelism* are quite different.

Committer's Guides
------------------

 * [Concurrency][concurrency]
 * [Debug Logging][debug_logging]
 * [Releasing][releasing]

 [cla]: https://spreadsheets.google.com/spreadsheet/viewform?formkey=dDViT2xzUHAwRkI3X3k5Z0lQM091OGc6MQ&ndplr=1
 [concurrency]: https://square.github.io/okhttp/concurrency/
 [debug_logging]: https://square.github.io/okhttp/debug_logging/

Committer's Guides
------------------

 * [Concurrency][concurrency]
 * [Debug Logging][debug_logging]
 * [Releasing][releasing]

 [cla]: https://spreadsheets.google.com/spreadsheet/viewform?formkey=dDViT2xzUHAwRkI3X3k5Z0lQM091OGc6MQ&ndplr=1
 [concurrency]: https://square.github.io/okhttp/concurrency/
 [debug_logging]: https://square.github.io/okhttp/debug_logging/

import java.time.Duration;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.CancellationException;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Future;
import java.util.concurrent.Semaphore;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;

        # Redirect all contributing pages to contribute/*
        'contributing.md': 'contribute/contributing.md'
        'code_of_conduct.md': 'contribute/code_of_conduct.md'
        'concurrency.md': 'contribute/concurrency.md'
        'debug_logging.md': 'contribute/debug_logging.md'

nav:
  - 'Overview':
    - 'Overview': index.md
    - 'Stack Overflow': https://stackoverflow.com/questions/tagged/okhttp?sort=active

  }

  /**
   * Guides the allowed concurrency among update operations. Used as a hint for internal sizing. The
   * table is internally partitioned to try to permit the indicated number of concurrent updates
   * without contention. Because assignment of entries to these partitions is not necessarily
   * uniform, the actual concurrency observed may vary. Ideally, you should choose a value to

import java.util.concurrent.Callable;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;
import org.jspecify.annotations.Nullable;

/**
 * Unit test for {@link FakeTicker}.
 *
 * @author Jige Yu
 */
@GwtCompatible

  }

  /**
   * Guides the allowed concurrency among update operations. Used as a hint for internal sizing. The
   * table is internally partitioned to try to permit the indicated number of concurrent updates
   * without contention. Because assignment of entries to these partitions is not necessarily
   * uniform, the actual concurrency observed may vary. Ideally, you should choose a value to