[jira] [Commented] (DIRSERVER-2234) Kinit via TCP causes ApacheDS to create a NioProcessor thread at 100% CPU

["Emmanuel Lecharny (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/DIRSERVER-2234?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16482435#comment-16482435 ] 

Emmanuel Lecharny commented on DIRSERVER-2234:
----------------------------------------------

Good catch !

I'll add the missing {{session.closeNow();}}

> Kinit via TCP causes ApacheDS to create a NioProcessor thread at 100% CPU
> -------------------------------------------------------------------------
>
>                 Key: DIRSERVER-2234
>                 URL: https://issues.apache.org/jira/browse/DIRSERVER-2234
>             Project: Directory ApacheDS
>          Issue Type: Bug
>    Affects Versions: 2.0.0-M24
>         Environment: ApacheDS
>            Reporter: Wenxiang Qiu
>            Priority: Major
>
> ApacheDS uses a KerberosProtocolHandler as the handler of the 
> IoAcceptor in KdcServer.java:
>  
> {code:java}
> // Inject the protocol handler acceptor.setHandler( new KerberosProtocolHandler( this, store ) );
> {code}
> When a TCP connection is about to be closed, KerberosProtocolHandler$inputClosed(IoSession session) is invoked when 
> {code:java}
> filterChain.fireInputClosed();
> {code}
> is reached in AbstractPollingIoProcessor.java. But KerberosProtocolHandler$inputClosed(IoSession session) does nothing:
> {code:java}
> public void inputClosed( IoSession session )
> {
> }
> {code}
> which leaves the session unclosed, which in turn prevents its SocketChannel from being deregistered from the selector in NioProcessor. As a result, 
> {code:java}
> int selected = select(SELECT_TIMEOUT);
> {code}
> in AbstractPollingIoProcessor.Processor.run() keeps returning a readable channel, on which read() returns -1. This infinite loop consumes all available CPU.
>  
> By constrast, LdapServer sets a LdapProtocolHandler to its acceptor, and LdapProtocolHandler inherits inputClosed(IoSession session) from IoHandlerAdapter:
> {code:java}
> public void inputClosed(IoSession session) throws Exception {
>     session.close(true);
> }
> {code}
> which closes properly the session.
>  
>  
> How to reproduce:
> Simply run kinit with TCP (by setting udp_preference_limit = 1 in /etc/krb5.conf), and ApacheDS will be running at 100% CPU. Doing it again will consume more CPU resources depending on core number.
>  



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)