driveCountMD = NewGaugeMD(driveCount,
		"Count of all drives")

	// iostat related
	driveReadsPerSecMD = NewGaugeMD(driveReadsPerSec,
		"Reads per second on a drive",
		allDriveLabels...)
	driveReadsKBPerSecMD = NewGaugeMD(driveReadsKBPerSec,
		"Kilobytes read per second on a drive",
		allDriveLabels...)
	driveReadsAwaitMD = NewGaugeMD(driveReadsAwait,
		"Average time for read requests served on a drive",
		allDriveLabels...)

 * limitations under the License.
 */

package com.google.common.util.concurrent;

import static java.util.concurrent.Executors.newFixedThreadPool;
import static java.util.concurrent.TimeUnit.SECONDS;

import com.google.common.annotations.GwtIncompatible;
import com.google.common.annotations.J2ktIncompatible;
import java.util.ArrayList;
import java.util.Random;
import java.util.concurrent.Callable;

     *
     * @return the remaining lifetime in seconds. If the default lifetime is
     *         used, this value have no meaning.
     *
     */
    public int getUserLifeTime() {
        return this.userLifetime;
    }

    /**
     * Set lifetime of current user.
     *
     * @param time
     *            the lifetime in seconds
     *
     */
    public void setUserLifeTime(int time) {

import static com.google.common.base.StandardSystemProperty.JAVA_SPECIFICATION_VERSION;
import static com.google.common.truth.Truth.assertThat;
import static java.lang.Integer.parseInt;
import static java.util.concurrent.TimeUnit.SECONDS;

import com.google.common.annotations.GwtIncompatible;
import com.google.common.annotations.J2ktIncompatible;
import java.lang.reflect.Method;
import java.util.concurrent.ExecutorService;

        } else if (minutes > 0) {
            return String.format("%02d:%02d min", minutes, seconds);
        } else {
            return String.format("%d.%03d s", seconds, millis);
        }
    }

    client =
      client
        .newBuilder()
        .connectionPool(ConnectionPool(0, 5, TimeUnit.SECONDS))
        .build()
    server.enqueue(
      MockResponse
        .Builder()
        .code(301)
        .addHeader("Location: /b")
        .bodyDelay(1, TimeUnit.SECONDS)
        .body("a")
        .build(),
    )
    server.enqueue(MockResponse(body = "b"))

   * @throws NullPointerException if both {@code first} and {@code second} are null
   * @since 18.0 (since 3.0 as {@code Objects.firstNonNull}).
   */
  public static <T> T firstNonNull(@Nullable T first, @Nullable T second) {
    if (first != null) {
      return first;
    }
    if (second != null) {
      return second;
    }
    throw new NullPointerException("Both parameters are null");
  }

import static com.google.common.util.concurrent.MoreExecutors.directExecutor;
import static java.util.concurrent.Executors.newScheduledThreadPool;
import static java.util.concurrent.TimeUnit.SECONDS;
import static org.junit.Assert.assertThrows;

import com.google.common.annotations.GwtCompatible;
import com.google.common.annotations.GwtIncompatible;
import com.google.common.annotations.J2ktIncompatible;

    // causing the thread to be suspended for 3.5 seconds, and then park itself for 2 seconds after
    // being resumed. To avoid a flake in this scenario, calculate how long that thread actually
    // waited and assert based on that time. Empirically, the race where the thread ends up waiting
    // for 5.5 seconds happens about 2% of the time.

	}, []string{"tier"}),
}

func (t *tierMetrics) Observe(tier string, dur time.Duration) {
	t.histogram.With(prometheus.Labels{"tier": tier}).Observe(dur.Seconds())
}

func (t *tierMetrics) logSuccess(tier string) {
	t.Lock()
	defer t.Unlock()

	stat := t.requestsCount[tier]
	stat.success++
	t.requestsCount[tier] = stat
}