CPU Hovers at 20-30% after OpenCensus has been added to a GCP AppEngine Flex service

Please answer these questions before submitting a bug report.

What version of OpenCensus are you using?

0.12.2

What JVM are you using (java -version)?

8

What did you do?

If possible, provide a recipe for reproducing the error. Include OpenCensus library in our build.gradle:

    compile "io.opencensus:opencensus-api:0.12.2"
    compile "io.opencensus:opencensus-exporter-trace-stackdriver:0.12.2"
    runtime "io.opencensus:opencensus-impl:0.12.2"

In Spring Boot using GCP AppEngine Flexible, we’ve defined a class to initialize the stackdriver exporter.

package com.jda.starter.utils.tracing;

import com.jda.starter.Application;

import io.opencensus.exporter.trace.stackdriver.StackdriverTraceConfiguration;
import io.opencensus.exporter.trace.stackdriver.StackdriverTraceExporter;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.context.annotation.Profile;
import org.springframework.context.event.ContextRefreshedEvent;
import org.springframework.context.event.EventListener;
import org.springframework.stereotype.Component;

import java.io.IOException;

@Component
@Profile(Application.Profiles.PRODUCTION)
public class OpenCensusExporterInitializer {

  private static final Logger LOGGER = LoggerFactory.getLogger(OpenCensusExporterInitializer.class);

  @EventListener(ContextRefreshedEvent.class)
  public void contextRefreshedEvent(ContextRefreshedEvent event) {
    initialize();
  }

  private void initialize() {
    try {
      StackdriverTraceExporter.createAndRegister(StackdriverTraceConfiguration.builder().build());
    } catch (IOException exception) {
      LOGGER.warn("Could not initialize OpenCensus export to Stackdriver");
    }
  }
}

What did you expect to see?

CPU to be close to 0 utilization when no traffic takes place.

What did you see instead?

CPU hovering between 20-30% once OpenCesus has been added to a service

[solatis]

I just ran into this issue as well, but not using AppEngine. Using VisualVM I saw that the crulpit was the OpenCensus.Disruptor-0 thread, so that confirms the investigation into Disruptor in this issue report.

Switching to -lite addresses the issue. Using 0.14 with the stackdriver exporter.

[bogdandrutu]

@steveniemitz see discussion in #1599 as well.