> > > > On 18/11/2022 10:21, Mark Thomas wrote: > > On 17/11/2022 20:01, Gonzalo Fernandez wrote: > > > > <snip/> > > > >>> The problem happens when a client with an open TCP / HTTP2 connection > >>> sends multiple incomplete streams, which seems to block the connection > >>> forever and not be able to accept new streams. > >>> > >>> In detail, using tcpdump, we are seeing that the Tomcat Server > >>> receives the HEADER frame, but never receives the following DATA > >>> frames for a stream. After 20 seconds (streamReadTimeout default > >>> value), the Tomcat Server throws a "client timeout" exception > >>> (stacktrace at the end of the mail), and returns "400 Bad Request" > >>> followed by a RST_STREAM frame. > >>> The problem is that when the amount of incomplete streams surpasses > >>> the value of "maxConcurrentStreams", the connection starts to return > >>> RST_STREAM to any new stream indefinitely, it never recovers. I > >>> verified this by changing the value of that property and looking at > >>> the number of streams in every connection. When the value wasn't > >>> defined, it took 100 incomplete streams over the same connection to > >>> break it, then I changed to 20 and it took 20 incomplete streams to > >>> break it. > >>> > >>> This makes me suspicious that the concurrent streams counter isn't > >>> being decreased when this happens, and could possibly be a bug. I > >>> tried to identify this in the tomcat codebase but I am not familiar > >>> enough with it. > > > > Thanks for the very detailed description. > > > > Your suspicion is correct. There is a Tomcat bug here. I have been able > > to write a test case that demonstrates the bug and am working on a fix. > > > > I just wanted to say how much the effort you put into researching this > > is appreciated. Your report has exactly the right amount of detail we > > need. Enough to see exactly what the problem is and to recreate the > > problem and no unnecessary extra information. > > > > I should have a patch for this shortly. > > Fixed in: > - 10.1.x for 10.1.3 onwards > - 9.0.x for 9.0.70 onwards > - 8.5.x for 8.5.85 onwards > > Mark > > --------------------------------------------------------------------- > To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org > For additional commands, e-mail: users-h...@tomcat.apache.org >
Thanks for the quick response. I appreciate your work. Have a great day. --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
