query use orderDesc is very slower than order

android 8.0 huawei P9
objectVersion：2.4.0

I inserted 12w pieces of data into Message table

@Entity
public class Message implements Serializable {

   @Id
    public long id;

    @Index
    private long serverId; 

    @Index
    private String sid;
    .......

}

the query method：

private void queryTest() {
       queryTest(1);
        queryTest(10);
        queryTest(50);
        queryTest(100);
        queryTest(1000);
        queryTest(3000);
        queryTest(6000);
        queryTest(10000);
}

private void queryTest(int queryNum) {
        long time = SystemClock.uptimeMillis();
        List<Message> messageList = Message.getMessageListByServerID2("k-007-liushengyun", Long.MIN_VALUE, queryNum);
        Log.d(TAG, "queryTest queryNum =" + queryNum + ",size=" + messageList.size() + ",orderTime=" + (SystemClock.uptimeMillis() - time));
        time = SystemClock.uptimeMillis();
        messageList = Message.getMessageListByServerID3("k-007-liushengyun", Long.MIN_VALUE, queryNum);
        Log.d(TAG, "queryTest queryNum =" + queryNum + ",size=" + messageList.size() + ",orderDescTime=" + (SystemClock.uptimeMillis() - time));
        messageList.clear();
    }

public static List<Message> getMessageListByServerID2(String sid, long minServerID, int count) {
        try {
            Query<Message> query = StoreManager.getBoxStore().boxFor(Message.class).query()
                    .equal(Message_.sid, sid)
                    .greater(Message_.serverId, minServerID).or().equal(Message_.serverId, minServerID)
                    .order(Message_.serverId).build();
            return count > 0 ? query.find(0, count) : query.find();
        } catch (Exception e) {
            SogouPlus.onException(e);
            return new LinkedList<>();
        }
    }

public static List<Message> getMessageListByServerID3(String sid, long minServerID, int count) {
        try {
            Query<Message> query = StoreManager.getBoxStore().boxFor(Message.class).query()
                    .equal(Message_.sid, sid)
                    .greater(Message_.serverId, minServerID).or().equal(Message_.serverId, minServerID)
                    .orderDesc(Message_.serverId).build();
            return count > 0 ? query.find(0, count) : query.find();
        } catch (Exception e) {
            SogouPlus.onException(e);
            return new LinkedList<>();
        }
    }

the query result:(ms)

queryTest queryNum =1,size=1,orderTime=71
queryTest queryNum =1,size=1,orderDescTime=301
queryTest queryNum =10,size=10,orderTime=72
queryTest queryNum =10,size=10,orderDescTime=581
queryTest queryNum =50,size=50,orderTime=73
queryTest queryNum =50,size=50,orderDescTime=908
queryTest queryNum =100,size=100,orderTime=75
queryTest queryNum =100,size=100,orderDescTime=1079
queryTest queryNum =1000,size=1000,orderTime=114
queryTest queryNum =1000,size=1000,orderDescTime=1952
queryTest queryNum =3000,size=3000,orderTime=175
queryTest queryNum =3000,size=3000,orderDescTime=2504
queryTest queryNum =6000,size=6000,orderTime=293
queryTest queryNum =6000,size=6000,orderDescTime=2846
queryTest queryNum =10000,size=10000,orderTime=483
queryTest queryNum =10000,size=10000,orderDescTime=3123

Commencez par les méthodes signalées getMessageListByServerID2 et getMessageListByServerID3, puis reproduisez queryTest sur Android 8.0 avec le jeu de données Message de 120 000 lignes. Comparez les temps d’exécution et les résultats de order et orderDesc ; le travail est terminé lorsque le comportement de la requête descendante est expliqué ou corrigé et couvert par une vérification de régression.