More data, it must have been a fluke because CompositeFilter.filter() still shows up high in the hot spot list of methods called. I do not have any Filter XML in my config...
Gary On Wed, Jul 8, 2015 at 4:20 PM, Gary Gregory <[email protected]> wrote: > Hi All: > > I am now profiling my JDBC driver and I was surprised to see Log4j's > CompositeFilter.filter() show up at 0.9% of CPU time when I had logging set > to INFO which only logged two events for the whole test run. The driver > does a lot of flow tracing at the TRACE level so Log4j gets called _a lot_. > > In my XML config, I have a Filters element with a bunch of Filter child > elements.When I am debugging, I comment some filters in and out. Most of > the time, I am not debugging, so I have all the individual filters > commented out. The top level Filters element is still there. > > If I completely remove all filters from the config (no Filters element), > then the CompositeFilter disappears from profiling. > > Now that I've looked at the code, I see that the behavior is explained by: > > @PluginFactory > public static CompositeFilter createFilters(@PluginElement("Filters") > final Filter[] filters) { > final List<Filter> filterList = filters == null || filters.length > == 0 ? > new ArrayList<Filter>() : Arrays.asList(filters); > return new CompositeFilter(filterList); > } > > An XML fragment like <Filters></Filters> always creates a CompositeFilter > even though there is nothing to filter. > > I'm not sure what is the best way to fix this. The CompositeFilter could > accept a null and treat it specially (not pretty or effective since > filter() still gets called a gazillion times). Ideally, the createFilters > should not even be called in the empty Filters element case. > > This is too nasty and obscure to put in the FAQ so I'd like to discuss how > to fix it. > > Thoughts? > > Thank you, > Gary > > -- > E-Mail: [email protected] | [email protected] > Java Persistence with Hibernate, Second Edition > <http://www.manning.com/bauer3/> > JUnit in Action, Second Edition <http://www.manning.com/tahchiev/> > Spring Batch in Action <http://www.manning.com/templier/> > Blog: http://garygregory.wordpress.com > Home: http://garygregory.com/ > Tweet! http://twitter.com/GaryGregory > -- E-Mail: [email protected] | [email protected] Java Persistence with Hibernate, Second Edition <http://www.manning.com/bauer3/> JUnit in Action, Second Edition <http://www.manning.com/tahchiev/> Spring Batch in Action <http://www.manning.com/templier/> Blog: http://garygregory.wordpress.com Home: http://garygregory.com/ Tweet! http://twitter.com/GaryGregory
