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https://issues.apache.org/jira/browse/IOTDB-1442?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17364642#comment-17364642
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WangChao commented on IOTDB-1442:
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Good job! Looking forward to the fix in 0.12.1.
> [Distributed] Time filter & TTL is not used during the construction of
> ClusterTimeGenerator
> -------------------------------------------------------------------------------------------
>
> Key: IOTDB-1442
> URL: https://issues.apache.org/jira/browse/IOTDB-1442
> Project: Apache IoTDB
> Issue Type: Bug
> Components: Core/Cluster
> Reporter: Tian Jiang
> Assignee: Tian Jiang
> Priority: Major
> Labels: cluster, query, time-generator
> Attachments: image-2021-06-17-09-50-28-254.png,
> image-2021-06-17-10-03-18-771.png
>
>
> When executing a read/write workload over an IoTDB cluster where queries
> involving value filters are included, the overall throughput decreases over
> time and the disk usage keeps increasing and is dominated by disk reads.
> We found out that the number of chunk reads was significantly high compared
> with the number of queries through profiling. Considering that the query time
> range was fixed, this phenomenon was abnormal.
> !image-2021-06-17-09-50-28-254.png|thumbnail!
> By intuition, we suspected that the time filter did not work expectedly and
> it turned a range query into a full query. So we checked the code where the
> readers are generated in the cluster module and found the following mistake
> that time filter is not provided during the reader construction. It seems
> that the time filter is included in the whole filter so it did not matter
> whether to pass it separately or not previously, but recent modifications
> required to extract it and pass it explicitly.
> !image-2021-06-17-10-03-18-771.png|thumbnail!
> The solution is rather simple, we can extract the time filter and pass it to
> the constructor so the time filter will not be missing.
> We also found out that TTL is not introduced during the reader construction,
> but it can be added readily.
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