[jira] [Created] (JAMES-3613) Avoid DNS resolution for protocol MDC context

["Benoit Tellier (Jira)" <se...@james.apache.org>]

Benoit Tellier created JAMES-3613:
-------------------------------------

             Summary: Avoid DNS resolution for protocol MDC context
                 Key: JAMES-3613
                 URL: https://issues.apache.org/jira/browse/JAMES-3613
             Project: James Server
          Issue Type: Improvement
          Components: IMAPServer, POP3Server, SMTPServer
    Affects Versions: 3.4.0, 3.5.0, 3.6.0
            Reporter: Benoit Tellier
             Fix For: 3.7.0


On gitter: {code:java}
Running into an odd issue after an application restart. (James 3.4.0 running in SpringBoot application). Was working fine, but now seem to be getting hung, or at least slow threads, on java.net.Inet6AddressImpl.getHostByAddr as called by org.apache.james.protocols.netty.ProtocolMDCContext.retrieveHost(ProtocolMDCContext.java:55). My environment is Java 11, on Amazon Linux 2, on EC2. 
{code}

https://gist.github.com/devondragon/8ec7424a48dc843338443b0b98356289

this seems to have been caused by too many incoming SMTP connections. Showed up in an odd way, but by decreasing the inbound connections this issue has stopped happening...

Likely some rate limit on DNS resolution. 

Proposal: switch from `getHostName` to `getHostString` to prevent the DNS resolution.



--
This message was sent by Atlassian Jira
(v8.3.4#803005)

---------------------------------------------------------------------
To unsubscribe, e-mail: server-dev-unsubscribe@james.apache.org
For additional commands, e-mail: server-dev-help@james.apache.org