[ 
https://issues.apache.org/jira/browse/LOG4J2-2399?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16574969#comment-16574969
 ] 

ASF GitHub Bot commented on LOG4J2-2399:
----------------------------------------

Github user bjlaub commented on a diff in the pull request:

    https://github.com/apache/logging-log4j2/pull/205#discussion_r208965737
  
    --- Diff: 
log4j-api/src/main/java/org/apache/logging/log4j/message/ReusableParameterizedMessage.java
 ---
    @@ -355,4 +352,35 @@ public void clear() { // LOG4J2-1583
             messagePattern = null;
             throwable = null;
         }
    +
    +    @Override
    +    public MessageContentFormatter getMessageContentFormatter() {
    +        return formatter;
    +    }
    +
    +    private static final MessageContentFormatter formatter = new 
MessageContentFormatter() {
    +        private final ThreadLocal<int[]> indices = new ThreadLocal<>();
    --- End diff --
    
    see 
https://github.com/apache/logging-log4j2/pull/208/commits/fc8ed21311d3a428b5a673a1b289ea2624e60cdb
 in #208 


> Reusable Messages do not respect log4j.format.msg.async
> -------------------------------------------------------
>
>                 Key: LOG4J2-2399
>                 URL: https://issues.apache.org/jira/browse/LOG4J2-2399
>             Project: Log4j 2
>          Issue Type: Task
>          Components: Core
>            Reporter: Carter Kozak
>            Assignee: Carter Kozak
>            Priority: Major
>
> Setting "log4j.format.msg.async" applies only to messages that do not 
> implement ReusableMessage.
> On applications using asynchronous logging with message formatting in the 
> background there is a measurable performance cost to using 
> ReusableParameterizedMessages instead of ParameterizedMessages due to 
> formatting on the application thread 
> (MutableLogEvent/RingBufferLogEvent.setMessage).
> I have a custom layout which does not log formatted messages in most cases, 
> but the format string and parameter values separately in order to analyze 
> values logged over time bucketed by logger name and format string. In this 
> case the formatting is unnecessary work. It is possible to implement a custom 
> message factory which doesn't format message data, however that would break 
> the ability to add a standard pattern layout in addition to the custom 
> formatter.
> h2. Proposed Design
> Our reusable events (MutableLogEvent and RingBufferLogEvent) currently 
> capture most of the required information, the format string and parameter 
> array, but are missing a bit of context for how the original message 
> implementation would format that data.
> ReusableMessage implementations may optionally extend 
> "MessageContentFormatterProvider"
> {code:java}
> interface MessageContentFormatterProvider {
>   MessageContentFormatter getMessageContentFormatter();
> }{code}
> Where MessageContentFormatter takes the form:
> {code:java}
> interface MessageContentFormatter {
>   void appendTo(StringBuilder dest, String format, Object[] params, short 
> paramCount);
> }{code}
> Reusable log event implementations will be updated to hold a reference to the 
> content formatter (instead of formatting to the local event buffer) when 
> asynchronous formatting is enabled _and_ the message is an instance of 
> MessageContentFormatterProvider.
>  



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

Reply via email to