presto-main/src/main/java/io/prestosql/operator/exchange/BroadcastExchanger.java/BroadcastExchanger/accept
class BroadcastExchanger:    @Override
    public void accept(Page page)
    {
        memoryManager.updateMemoryUsage(page.getRetainedSizeInBytes());

        PageReference pageReference = new PageReference(page, buffers.size(), () -> memoryManager.updateMemoryUsage(-page.getRetainedSizeInBytes()));

        for (Consumer<PageReference> buffer : buffers) {
            buffer.accept(pageReference);
        }
    }