On 12/19/20 9:13 AM, Jens Axboe wrote: > On 12/18/20 7:49 PM, Josef wrote: >>> I'm happy to run _any_ reproducer, so please do let us know if you >>> manage to find something that I can run with netty. As long as it >>> includes instructions for exactly how to run it :-) >> >> cool :) I just created a repo for that: >> https://github.com/1Jo1/netty-io_uring-kernel-debugging.git >> >> - install jdk 1.8 >> - to run netty: ./mvnw compile exec:java >> -Dexec.mainClass="uring.netty.example.EchoUringServer" >> - to run the echo test: cargo run --release -- --address >> "127.0.0.1:2022" --number 200 --duration 20 --length 300 >> (https://github.com/haraldh/rust_echo_bench.git) >> - process kill -9 >> >> async flag is enabled and these operation are used: OP_READ, >> OP_WRITE, OP_POLL_ADD, OP_CLOSE, OP_ACCEPT >> >> (btw you can change the port in EchoUringServer.java) > > This is great! Not sure this is the same issue, but what I see here is > that we have leftover workers when the test is killed. This means the > rings aren't gone, and the memory isn't freed (and unaccounted), which > would ultimately lead to problems of course, similar to just an > accounting bug or race. > > The above _seems_ to be related to IOSQE_ASYNC. Trying to narrow it > down... Further narrowed down, it seems to be related to IOSQE_ASYNC on the read requests. I'm guessing there are cases where we end up not canceling them on ring close, hence the ring stays active, etc. If I just add a hack to clear IOSQE_ASYNC on IORING_OP_READ, then the test terminates fine on the kill -9. -- Jens Axboe
