public int duration() {
        if (isInfiniteMin()) {
            return Integer.MIN_VALUE;
        }
        if (isInfiniteMax()) {
            return Integer.MAX_VALUE;
        }
        return Integer.parseInt(this.max) - Integer.parseInt(this.min);
    }
The max value of this bucket representing.
oap-server/server-core/src/main/java/org/apache/skywalking/oap/server/core/query/type/Bucket.java