private void init(final StateStore root) {
        taskId = context.taskId().toString();
        streamsMetrics = context.metrics();

        bufferSizeSensor = StateStoreMetrics.suppressionBufferSizeSensor(
            taskId,
            METRIC_SCOPE,
            storeName,
            streamsMetrics
        );
        bufferCountSensor = StateStoreMetrics.suppressionBufferCountSensor(
            taskId,
            METRIC_SCOPE,
            storeName,
            streamsMetrics
        );

        this.context.register(root, (RecordBatchingStateRestoreCallback) this::restoreBatch);
        updateBufferMetrics();
        open = true;
        partition = context.taskId().partition();
    }
As of 2.1, there's no way for users to directly interact with the buffer,
so this method is implemented solely to be called by Streams (which
it will do based on the {@code cache.max.bytes.buffering} config.
<p>
It's currently a no-op.
streams/src/main/java/org/apache/kafka/streams/state/internals/InMemoryTimeOrderedKeyValueChangeBuffer.java