dgarson commented on a change in pull request #685: SOLR-13434: OpenTracing support for Solr URL: https://github.com/apache/lucene-solr/pull/685#discussion_r288232939
########## File path: solr/core/src/java/org/apache/solr/core/TracerConfigurator.java ########## @@ -0,0 +1,63 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +package org.apache.solr.core; + +import java.lang.invoke.MethodHandles; +import java.util.Map; + +import io.opentracing.Tracer; +import io.opentracing.noop.NoopTracerFactory; +import org.apache.solr.common.cloud.ClusterPropertiesListener; +import org.apache.solr.common.cloud.ZkStateReader; +import org.apache.solr.util.plugin.NamedListInitializedPlugin; +import org.apache.solr.util.tracing.GlobalTracer; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +public abstract class TracerConfigurator implements NamedListInitializedPlugin { + private static final Logger log = LoggerFactory.getLogger(MethodHandles.lookup().lookupClass()); + + public abstract Tracer getTracer(); + + public static void loadTracer(SolrResourceLoader loader, PluginInfo info, ZkStateReader stateReader) { + if (info == null) { + GlobalTracer.setup(NoopTracerFactory.create()); + GlobalTracer.setSamplePercentage(0.0); + } else { + TracerConfigurator configurator = loader + .newInstance(info.className, TracerConfigurator.class); + configurator.init(info.initArgs); + + GlobalTracer.setup(configurator.getTracer()); + + stateReader.registerClusterPropertiesListener(properties -> { + if (properties.containsKey(ZkStateReader.SAMPLE_PERCENTAGE)) { + try { + double sampleRate = Double.parseDouble(properties.get(ZkStateReader.SAMPLE_PERCENTAGE).toString()); + GlobalTracer.setSamplePercentage(sampleRate); + } catch (NumberFormatException e) { + log.error("Unable to set sample rate", e); + } + } else { + GlobalTracer.setSamplePercentage(1); Review comment: Tracing at 100% could generate a lot of trace data. The default sample rate for many tracers like Zipkin is 0.1%. Do we want to use a lower default or do we really want to trace everything in the event that no explicit rate is defined? ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected] With regards, Apache Git Services --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
