run() — netty Function Reference

Architecture documentation for the run() function in ThreadDeathWatcher.java from the netty codebase.

Function java CommonUtil Logging calls 4 called by 2

Entity Profile

CommonUtil→ Logging→ run() — netty Function Reference

Dependency Diagram

graph TD
  2e12d8f3_2a76_c115_2e1f_27af3c853d54["run()"]
  5f6d0707_3005_8256_7c2d_19661826552d["Watcher"]
  2e12d8f3_2a76_c115_2e1f_27af3c853d54 -->|defined in| 5f6d0707_3005_8256_7c2d_19661826552d
  52d983df_3c33_cc34_17dc_62af3798f3ef["schedule()"]
  52d983df_3c33_cc34_17dc_62af3798f3ef -->|calls| 2e12d8f3_2a76_c115_2e1f_27af3c853d54
  666cccad_fc12_bc19_59b3_051276b803c6["notifyWatchees()"]
  666cccad_fc12_bc19_59b3_051276b803c6 -->|calls| 2e12d8f3_2a76_c115_2e1f_27af3c853d54
  d63c9c90_1e42_7586_aab0_7f19f87736ba["fetchWatchees()"]
  2e12d8f3_2a76_c115_2e1f_27af3c853d54 -->|calls| d63c9c90_1e42_7586_aab0_7f19f87736ba
  666cccad_fc12_bc19_59b3_051276b803c6["notifyWatchees()"]
  2e12d8f3_2a76_c115_2e1f_27af3c853d54 -->|calls| 666cccad_fc12_bc19_59b3_051276b803c6
  d0ccf1bb_8ca7_fdeb_a3d1_eecc0fd357d4["watch()"]
  2e12d8f3_2a76_c115_2e1f_27af3c853d54 -->|calls| d0ccf1bb_8ca7_fdeb_a3d1_eecc0fd357d4
  bcd89545_0ae1_7935_4b1c_1e03947be6b7["unwatch()"]
  2e12d8f3_2a76_c115_2e1f_27af3c853d54 -->|calls| bcd89545_0ae1_7935_4b1c_1e03947be6b7
  style 2e12d8f3_2a76_c115_2e1f_27af3c853d54 fill:#6366f1,stroke:#818cf8,color:#fff

Relationship Graph

Source Code

common/src/main/java/io/netty/util/ThreadDeathWatcher.java lines 150–195

        @Override
        public void run() {
            for (;;) {
                fetchWatchees();
                notifyWatchees();

                // Try once again just in case notifyWatchees() triggered watch() or unwatch().
                fetchWatchees();
                notifyWatchees();

                try {
                    Thread.sleep(1000);
                } catch (InterruptedException ignore) {
                    // Ignore the interrupt; do not terminate until all tasks are run.
                }

                if (watchees.isEmpty() && pendingEntries.isEmpty()) {

                    // Mark the current worker thread as stopped.
                    // The following CAS must always success and must be uncontended,
                    // because only one watcher thread should be running at the same time.
                    boolean stopped = started.compareAndSet(true, false);
                    assert stopped;

                    // Check if there are pending entries added by watch() while we do CAS above.
                    if (pendingEntries.isEmpty()) {
                        // A) watch() was not invoked and thus there's nothing to handle
                        //    -> safe to terminate because there's nothing left to do
                        // B) a new watcher thread started and handled them all
                        //    -> safe to terminate the new watcher thread will take care the rest
                        break;
                    }

                    // There are pending entries again, added by watch()
                    if (!started.compareAndSet(false, true)) {
                        // watch() started a new watcher thread and set 'started' to true.
                        // -> terminate this thread so that the new watcher reads from pendingEntries exclusively.
                        break;
                    }

                    // watch() added an entry, but this worker was faster to set 'started' to true.
                    // i.e. a new watcher thread was not started
                    // -> keep this thread alive to handle the newly added entries.
                }
            }
        }