testThreadCacheDestroyed() — netty Function Reference

Source Code

buffer/src/test/java/io/netty/buffer/PooledByteBufAllocatorTest.java lines 371–424

    private static void testThreadCacheDestroyed(boolean useRunnable) throws InterruptedException {
        int numArenas = 11;
        final PooledByteBufAllocator allocator =
            new PooledByteBufAllocator(numArenas, numArenas, 8192, 1);

        final AtomicBoolean threadCachesCreated = new AtomicBoolean(true);

        final Runnable task = new Runnable() {
            @Override
            public void run() {
                ByteBuf buf = allocator.newHeapBuffer(1024, 1024);
                for (int i = 0; i < buf.capacity(); i++) {
                    buf.writeByte(0);
                }

                // Make sure that thread caches are actually created,
                // so that down below we are not testing for zero
                // thread caches without any of them ever having been initialized.
                if (allocator.metric().numThreadLocalCaches() == 0) {
                    threadCachesCreated.set(false);
                }

                buf.release();
            }
        };

        for (int i = 0; i < numArenas; i++) {
            final FastThreadLocalThread thread;
            if (useRunnable) {
                thread = new FastThreadLocalThread(task);
                assertTrue(thread.willCleanupFastThreadLocals());
            } else {
                thread = new FastThreadLocalThread() {
                    @Override
                    public void run() {
                        task.run();
                    }
                };
                assertFalse(thread.willCleanupFastThreadLocals());
            }
            thread.start();
            thread.join();
        }

        // Wait for the ThreadDeathWatcher to have destroyed all thread caches
        while (allocator.metric().numThreadLocalCaches() > 0) {
            // Signal we want to have a GC run to ensure we can process our ThreadCleanerReference
            System.gc();
            System.runFinalization();
            LockSupport.parkNanos(MILLISECONDS.toNanos(100));
        }

        assertTrue(threadCachesCreated.get());
    }