[jira] [Commented] (IOTDB-4581) Compression Ratio compute error

["Haiming Zhu (Jira)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/IOTDB-4581?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17616877#comment-17616877 ] 

Haiming Zhu commented on IOTDB-4581:
------------------------------------

This is not a bug, but maybe we should find a better way to compute compression ratio.

This phenomenon is caused by tsfile contains few series whose data can be compressed with high compression ratio. Take avg_series_point_num_threshold=5000 as an example:

 

*Scenario 1.* Small TsFile with high compression ratio, It's 

 

*Scenario 2.* Small TsFile with low compression ratio

 

> Compression Ratio compute error
> -------------------------------
>
>                 Key: IOTDB-4581
>                 URL: https://issues.apache.org/jira/browse/IOTDB-4581
>             Project: Apache IoTDB
>          Issue Type: Bug
>            Reporter: Jialin Qiao
>            Assignee: Haiming Zhu
>            Priority: Minor
>         Attachments: high ratio data.png, high ratio log.png, low ratio data.png, low ratio log.png
>
>
> We try to read a tsfile and write it to IoTDB with different config but in same version. If we set the avg_series_point_num_threshold to 5000, 10000 and 100000, IoTDB computes compression rate as 100, 10 and 3. But the file size in the disk is the same. The compression ratio must be computed wrong. 



--
This message was sent by Atlassian Jira
(v8.20.10#820010)