void setValues(long inTs, long inGcPause) {
      this.ts = inTs;
      this.gcPause = inGcPause;
    }
Returns the percentage (0..100) of time that the JVM spent in GC pauses within the
observation window of the associated GCTimeMonitor.

@return GcTimePercentage.
iotdb-core/node-commons/src/main/java/org/apache/iotdb/commons/service/metric/JvmGcMonitorMetrics.java