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https://issues.apache.org/jira/browse/LOG4NET-415?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13875826#comment-13875826
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Stefan Bodewig commented on LOG4NET-415:
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Thanks for your persistence Jose Luis

First of all I'd wish to find more time :-(

Well, 

* I'd leave all async stuff out and rather try to get one of the proposed 
general purpose AsyncAppenders into shape.
* I'd make non-blocking an option but change the documentation to clearly state 
this may lead to lost logs
* I'd try to find a better name for the StrictRFC3164 property that better says 
what it does.  Then again I've never been good at names.

At least for the StrictRFC3164 part we could use a unit test or two, I don't 
think writing tests for the blocking part will be easy.  You don't really need 
to resubmit your patch, I can modify it myself, but you may be faster than me.

> RemoteSyslogAppender may block for ARP resolution + Improvement Strict RFC3164
> ------------------------------------------------------------------------------
>
>                 Key: LOG4NET-415
>                 URL: https://issues.apache.org/jira/browse/LOG4NET-415
>             Project: Log4net
>          Issue Type: Bug
>          Components: Appenders
>    Affects Versions: 1.2.13
>         Environment: Any Windows environment
>            Reporter: Jose Luis Pedrosa
>              Labels: RemoteSyslogAppender
>         Attachments: LOG4NET-415.patch, MessageLostTest.cs, 
> MessageLostTest.cs, MessageLostTestAsync.cs, RemoteSyslogNonBlockingv2.patch
>
>
> Sending UDP packages may block for some time in specific circumstances:
> 1) Next hop in network level 3 can't be resolved by ARP.
> 2) Datagram size exceeds FastSendDatagramThreshold configured size.
> When sending packets bigger than FastSendDatagramThreshold, the OS waits 
> until the packet is actually sent, if the If the syslog (or the next hop to 
> reach the syslog) is in the same VLAN/Subnet the OS tries to resolve by ARP 
> the Ip of the configured syslog, this may take up to 3 seconds, slowing down 
> the whole application, which in some cases can lead to outages (timeouts, DB 
> locks...).
> Also the fact that each carriage return generates the headers of the packet 
> again, that can lead to a significant overhead in some scenarios, for 
> instance when loggign HTTP requests to a remote syslog, every header will go 
> in a different message. Also some logging may require characters that are now 
> skipped in patch:  https://issues.apache.org/jira/browse/LOG4NET-370
> I'm adding a patch that
> 1) Moves the use of UDPClient to Non blocking sockets, which eliminates the 
> blocking. 
> 2) Adds a configuration field to decide if you want Strict RFC Behaviour or 
> not (with default Strict).
> Please your feedback, thanks in advance
> Jose Luis



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