当我使用分页查询二级索引时，当数据增长时，查询速度会变慢。
我认为使用分页，无论数据增长多大，查询一个页面都需要相同的时间。是真的吗？为什么我的查询速度变慢了？
我的简化表是

CREATE TABLE closed_executions (
  domain_id            uuid,
  workflow_id          text,
  start_time           timestamp,
  workflow_type_name   text,
  PRIMARY KEY  ((domain_id), start_time)
) WITH CLUSTERING ORDER BY (start_time DESC)
  AND COMPACTION = {
    'class': 'org.apache.cassandra.db.compaction.LeveledCompactionStrategy'
  }
  AND GC_GRACE_SECONDS = 172800;

我创建了一个二级索引

CREATE INDEX closed_by_type ON closed_executions (workflow_type_name);

我用以下cql查询

SELECT workflow_id, start_time, workflow_type_name 
FROM closed_executions 
WHERE domain_id = ? 
AND start_time >= ? 
AND start_time <= ? 
AND workflow_type_name = ?

和代码

query := v.session.Query(templateGetClosedWorkflowExecutionsByType,
        request.DomainUUID,
        common.UnixNanoToCQLTimestamp(request.EarliestStartTime),
        common.UnixNanoToCQLTimestamp(request.LatestStartTime),
        request.WorkflowTypeName).Consistency(gocql.One)
iter := query.PageSize(request.PageSize).PageState(request.NextPageToken).Iter()
// PageSize is 10, but could be thousand

环境：
macbook pro系列
Cassandra：3.11.0
gocql:github.com/gocql/gocql-master
观察：
10k排，秒以内
10万排，约3秒
1米排，约17秒
调试日志：

INFO  [ScheduledTasks:1] 2018-09-11 16:29:48,349 NoSpamLogger.java:91 - Some operations were slow, details available at debug level (debug.log)
DEBUG [ScheduledTasks:1] 2018-09-11 16:29:48,357 MonitoringTask.java:173 - 1 operations were slow in the last 5005 msecs:
<SELECT * FROM cadence_visibility.closed_executions WHERE workflow_type_name = code.uber.internal/devexp/cadence-bench/load/basic.stressWorkflowExecute AND token(domain_id, domain_partition) >= token(d3138e78-abe7-48a0-adb9-8c466a9bb3fa, 0) AND token(domain_id, domain_partition) <= token(d3138e78-abe7-48a0-adb9-8c466a9bb3fa, 0) AND start_time >= 2018-09-11 16:29-0700 AND start_time <= 1969-12-31 16:00-0800 LIMIT 10>, time 2747 msec - slow timeout 500 msec
DEBUG [COMMIT-LOG-ALLOCATOR] 2018-09-11 16:31:47,774 AbstractCommitLogSegmentManager.java:107 - No segments in reserve; creating a fresh one
DEBUG [ScheduledTasks:1] 2018-09-11 16:40:22,922 ColumnFamilyStore.java:899 - Enqueuing flush of size_estimates: 23.997MiB (2%) on-heap, 0.000KiB (0%) off-heap

相关参考（我的问题没有答案）：
https://lists.apache.org/thread.html/%3ccaaikobidknhvoz8oqqmnczfzhdfidfw6hts63vxxcohisqyzgg@mail.gmail.com%3e
https://www.datastax.com/dev/blog/cassandra-native-secondary-index-deep-dive
https://docs.datastax.com/en/developer/java-driver/3.2/manual/paging/
--编辑表状态返回

Total number of tables: 105

----------------
Keyspace : cadence_visibility
    Read Count: 19
    Read Latency: 0.5125263157894736 ms.
    Write Count: 3220964
    Write Latency: 0.04900822269357869 ms.
    Pending Flushes: 0
        Table: closed_executions
        SSTable count: 1
        SSTables in each level: [1, 0, 0, 0, 0, 0, 0, 0, 0]
        Space used (live): 20.3 MiB
        Space used (total): 20.3 MiB
        Space used by snapshots (total): 0 bytes
        Off heap memory used (total): 6.35 KiB
        SSTable Compression Ratio: 0.40192660515179696
        Number of keys (estimate): 3
        Memtable cell count: 28667
        Memtable data size: 7.35 MiB
        Memtable off heap memory used: 0 bytes
        Memtable switch count: 9
        Local read count: 9
        Local read latency: NaN ms
        Local write count: 327024
        Local write latency: NaN ms
        Pending flushes: 0
        Percent repaired: 0.0
        Bloom filter false positives: 0
        Bloom filter false ratio: 0.00000
        Bloom filter space used: 16 bytes
        Bloom filter off heap memory used: 8 bytes
        Index summary off heap memory used: 38 bytes
        Compression metadata off heap memory used: 6.3 KiB
        Compacted partition minimum bytes: 150
        Compacted partition maximum bytes: 62479625
        Compacted partition mean bytes: 31239902
        Average live cells per slice (last five minutes): NaN
        Maximum live cells per slice (last five minutes): 0
        Average tombstones per slice (last five minutes): NaN
        Maximum tombstones per slice (last five minutes): 0
        Dropped Mutations: 0 bytes

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