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https://issues.apache.org/jira/browse/LOG4J2-585?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13960989#comment-13960989
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Ralph Goers commented on LOG4J2-585:
------------------------------------

You mention that your code is slower so long as the marker depth is less than 
5. I would guess that means that about 98% of the time it will be slower and 
about 50% of the time it will be 3 times slower.  I would not be in favor of 
that.

I will take a look at this this weekend and see how this can be done.

I'd also really like to understand a real use case you might have for 
dynamically changing Markers.  Without that requirement it would be easy to 
just add {code}
getMarker(String name, String[] parents)
getMarker(String name, Marker[] parents)
{code}
to MarkerManager with what I would imagine to be very little impact.

> Markers not as powerful as slf4j
> --------------------------------
>
>                 Key: LOG4J2-585
>                 URL: https://issues.apache.org/jira/browse/LOG4J2-585
>             Project: Log4j 2
>          Issue Type: Improvement
>          Components: API
>    Affects Versions: 2.0-rc1
>            Reporter: Bruce Brouwer
>         Attachments: log4j2-585-concept.patch
>
>
> Log4J's markers are not as flexible as markers in SLF4J. 
> First, SLF4J's markers are mutable. By allowing markers to be mutable, I can 
> change the relationship of markers to each other based upon runtime or 
> business conditions. 
> Second, and more importantly I think, is that essentially SLF4J markers have 
> this parent/child relationship, much like Log4J, except that in SLF4J, I can 
> essentially have a marker with multiple parents. For example, I might want 
> this structure:
> * Animal
> ** Bird
> *** Duck
> ** Mammal
> *** Bear
> *** Dolphin
> * Travels by
> ** Water
> *** Duck
> *** Dolphin
> ** Land
> *** Duck
> *** Bear
> ** Air
> *** Duck
> Of course, this is a contrived example, but I wanted to describe the 
> relationships. Now, if I wanted to filter based on markers that travel by 
> Water for some appenders, and another appender wants to filter by Mammals, I 
> can't simply use the single marker of Dolphin. 
> Either we need to reverse the marker relationship so that it contains its 
> children, much like SLF4J, or we allow markers to have multiple parents, 
> which I prefer because it could make it more succinct to define:
> {code}
> private static final Marker BY_LAND = MarkerManager.getMarker("BY_LAND");
> private static final Marker BY_WATER = MarkerManager.getMarker("BY_WATER");
> private static final Marker DUCK = MarkerManager.getMarker("DUCK", BY_LAND, 
> BY_WATER);
> {code}
> As for the Marker API, we would either need to change getParent to 
> getParents, or get rid of the getParent method from the API and just rely on 
> the isInstanceOf method to handle checking multiple parents by looking at 
> private member variables (my preference)



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