Generating test coverage reports for Elasticsearch is currently not possible through Gradle.
However, it _is_ possible to gain insight in code coverage using IntelliJ's built-in coverage
analysis tool that can measure coverage upon executing specific tests. Eclipse may also be able
to do the same using the EclEmma plugin.

Test coverage reporting used to be possible with JaCoCo when Elasticsearch was using Maven

   * calling thread wait for that time.
   *
   * The simplest way to maintain a rate of QPS is to keep the timestamp of the last granted
   * request, and ensure that (1/QPS) seconds have elapsed since then. For example, for a rate of
   * QPS=5 (5 tokens per second), if we ensure that a request isn't granted earlier than 200ms after
   * the last one, then we achieve the intended rate. If a request comes and the last request was

    RateLimiter rateLimiter = new SmoothWarmingUp(stopwatch, warmupPeriod, unit, coldFactor);
    rateLimiter.setRate(permitsPerSecond);
    return rateLimiter;
  }

  /**
   * The underlying timer; used both to measure elapsed time and sleep as necessary. A separate
   * object to facilitate testing.
   */
  private final SleepingStopwatch stopwatch;

        // Data: bitSize / 8 bytes
        long predictedSize = bf.bitSize() / 8 + 6;
        assertThat(bf.serializedSize()).isEqualTo(predictedSize);

        // Serialize and measure actual size
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        bf.writeTo(out);
        int actualSize = out.size();
        assertThat(bf.serializedSize()).isEqualTo(actualSize);

    CIFSContext context = getTestContext();
    context.getConfig().setProperty("jcifs.smb.client.useRDMA", "true");
    
    SmbFile file = new SmbFile("smb://server/share/largefile.dat", context);
    
    // Measure RDMA transfer performance
    byte[] data = new byte[10485760];  // 10MB
    Arrays.fill(data, (byte)0x42);
    
    long start = System.currentTimeMillis();
    
    try (OutputStream os = file.getOutputStream()) {

 * may cause corruption or runtime errors if not. It may however be shared amongst multiple OkHttpClient
 * instances.
 *
 * ## Cache Optimization
 *
 * To measure cache effectiveness, this class tracks three statistics:
 *
 *  * **[Request Count:][requestCount]** the number of HTTP requests issued since this cache was
 *    created.

You could put an **arbitrary number** to target, for example, something **between 50% to 90%** of resource utilization. The point is that those are probably the main things you will want to measure and use to tweak your deployments.

				totalDownloadTTFB = append(totalDownloadTTFB, throughputHighestResults[i].DownloadTTFB...)
			}

			result.PUTStats.Response = totalUploadTimes.Measure()
			result.GETStats.Response = totalDownloadTimes.Measure()
			result.GETStats.TTFB = totalDownloadTTFB.Measure()

			result.Size = opts.objectSize
			result.Disks = globalEndpoints.NEndpoints()
			result.Servers = len(globalNotificationSys.peerClients) + 1

        return Strings.fromOEMBytes(src, srcIndex, Strings.findTermination(src, srcIndex, maxLen), getConfig());
    }

    /**
     * Calculates the wire format length of a string
     * @param str string to measure
     * @param offset current buffer offset for alignment calculation
     * @return string length
     */
    public int stringWireLength(final String str, final int offset) {
        int len = str.length() + 1;

  No covered work shall be deemed part of an effective technological
measure under any applicable law fulfilling obligations under article
11 of the WIPO copyright treaty adopted on 20 December 1996, or
similar laws prohibiting or restricting circumvention of such
measures.

  When you convey a covered work, you waive any legal power to forbid
circumvention of technological measures to the extent such circumvention