Issue with QuicCodecDispatcher

[poisonriver]

Hi @normanmaurer ,
I'm trying to utilize QuicCodecDispatcher and noticed that a number of QuicheQuicChannel instances are increasing with time on my server (when http clients come and leave) thus creating a leak. I removed QuicCodecDispatcher from the server initialization and the problem disappeared. Then I added logging for QuicChannel init and Http3 request processing (Http3RequestStreamInboundHandler.channelRead) and noticed the following:

• Using Curl: 1 packet come from client during Quic connection establishment (Initial) and 1 QuichChannel init call happens
• Using Chrome : 5 packets come from a client during Quic connection establishment (Initial, 0-RTT, 0-RTT, Initial, Initial) and 5 QuichChannel init calls happen, while Http3 request is being processed only in one of these QuicChannels.

My server initialization code is below, Wireshark screenshot are attached. Can you please advise if I'm missing something or there's some other issue?

        Bootstrap bootstrap = new Bootstrap().group(nioEventLoopGroup)
                .channel(EpollDatagramChannel.class)
                .option(EpollChannelOption.SO_REUSEPORT, true)
                .handler(new QuicCodecDispatcher() {
                    @Override
                    protected void initChannel(Channel channel, int localConnectionIdLength, QuicConnectionIdGenerator idGenerator) throws Exception {
                        QuicServerCodecBuilder codecBuilder = Http3.newQuicServerCodecBuilder()
                                .localConnectionIdLength(localConnectionIdLength)
                                .connectionIdAddressGenerator(idGenerator)
                                .sslContext(sslContext)
                                .maxIdleTimeout(10000, TimeUnit.MILLISECONDS)
                                .handler(new ChannelInitializer<QuicChannel>() {
                                    protected void initChannel(QuicChannel ch) {
                                        log.info("QuicChannel init: " + ch.id());
                                        ch.pipeline().addLast(new Http3ServerConnectionHandler(
                                                new ChannelInitializer<QuicStreamChannel>() {
                                                    @Override
                                                    protected void initChannel(QuicStreamChannel ch) {
                                                        ch.pipeline().addLast(new Http3RequestStreamInboundHandler() {
                                                            @Override
                                                            protected void channelRead(ChannelHandlerContext ctx, Http3HeadersFrame frame) throws Exception {
                                                            }

                                                            @Override
                                                            protected void channelRead(ChannelHandlerContext ctx, Http3DataFrame frame) throws Exception {
                                                            }

                                                            @Override
                                                            protected void channelInputClosed(ChannelHandlerContext ctx) throws Exception {
                                                            }

                                                        });
                                                    }
                                                }, null, null, null, true)
                                        );
                                    }
                                });
                        channel.pipeline().addLast(codecBuilder.build());
                    }
                });
        for (int i = 0; i < threadsPerAddress; i++) {
            Channel quicChannel = bootstrap
                    .bind(address, port).sync().channel();
            quicChannels.add(quicChannel);
        }

[normanmaurer]

Can you also take a heap dump and share it ?

[poisonriver]

Hi @normanmaurer ,
heap dump (made with option 'live' ) attached
netty-dump.bin.gz

[poisonriver]

Hi @normanmaurer ,
Did you have a chance to look through the heap dump?

[normanmaurer]

Sorry these last few weeks been super busy. I will pick it up next week

[normanmaurer]

@poisonriver hmm... in the heap dump I only see 10 QuicheQuicChannel instances.

[normanmaurer]

@poisonriver I am pretty sure this should fix what you did see #720

[normanmaurer]

Fixed by #720 and #721

[poisonriver]

Hi @normanmaurer ,
Thank you, looks like this is the issue, I will test it soon

@poisonriver I am pretty sure this should fix what you did see #720

[normanmaurer]

@poisonriver keep me posted

[normanmaurer]

@poisonriver any updates ?

[poisonriver]

@poisonriver any updates ?

Hi @normanmaurer
ran some tests, looks like nothing leaks now, thank you!
side question: is there any reason for not exposing initial congestion window from the Quiche config?

[normanmaurer]

@poisonriver any updates ?

Hi @normanmaurer ran some tests, looks like nothing leaks now, thank you! side question: is there any reason for not exposing initial congestion window from the Quiche config?

Nope... PRs welcome :)

[poisonriver]

@poisonriver any updates ?

Hi @normanmaurer ran some tests, looks like nothing leaks now, thank you! side question: is there any reason for not exposing initial congestion window from the Quiche config?

Nope... PRs welcome :)

PR is created