I would imagine this to be true. The normal use case is request and response. Additional synchronization makes the code run slower in that scenario. I would suggest synchronizing critical paths.
I have to synchronize write paths for the same reason where one input may write to dozens of other sockets. On Nov 21, 2013 10:23 AM, "Alexandros Touloupis" <[email protected]> wrote: > Hello all, > > I am using mina 2.0.8 since I needed a patch included in this release. > > I face the following problem: > > The concept of the application is to "multiplex" inbound to outbound > connections in MINA. This means that there might be 2 incoming connections > that are multiplexed in one outbound connection. During my tests i randomly > see this exception: > > java.nio.InvalidMarkException > at java.nio.Buffer.reset(Buffer.java:298) ~[?:1.7.0_40] > at > > org.apache.mina.core.buffer.AbstractIoBuffer.reset(AbstractIoBuffer.java:414) > ~[mina-core-2.0.8-PATCHED.jar:?] > at > > org.apache.mina.core.polling.AbstractPollingIoProcessor.writeBuffer(AbstractPollingIoProcessor.java:926) > ~[mina-core-2.0.8-SNAPSHOT.jar:?] > at > > org.apache.mina.core.polling.AbstractPollingIoProcessor.flushNow(AbstractPollingIoProcessor.java:844) > [mina-core-2.0.8-SNAPSHOT.jar:?] > at > > org.apache.mina.core.polling.AbstractPollingIoProcessor.flush(AbstractPollingIoProcessor.java:772) > [mina-core-2.0.8-SNAPSHOT.jar:?] > at > > org.apache.mina.core.polling.AbstractPollingIoProcessor.access$700(AbstractPollingIoProcessor.java:67) > [mina-core-2.0.8-SNAPSHOT.jar:?] > at > > org.apache.mina.core.polling.AbstractPollingIoProcessor$Processor.run(AbstractPollingIoProcessor.java:1112) > [mina-core-2.0.8-SNAPSHOT.jar:?] > at > > org.apache.mina.util.NamePreservingRunnable.run(NamePreservingRunnable.java:64) > [mina-core-2.0.8-SNAPSHOT.jar:?] > at > > java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) > [?:1.7.0_40] > at > > java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) > [?:1.7.0_40] > at java.lang.Thread.run(Thread.java:724) [?:1.7.0_40] > > After some investigation i noticed that this happened when 2 threads > decided to write to the same IoSession a message the same time. My > assumption is that the #IoSession.write method is not thread safe, thus i > synchronized the session instance before executing the write method in my > handlers and up until now i haven't faced the same issue. Is my assumption > valid? > > Thank you in advance, > Alex >
