[jira] [Commented] (AIRFLOW-5096) reduce the number of times the pickle is inserted into the database by modifying the hash field of Dag

["ASF GitHub Bot (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/AIRFLOW-5096?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16898649#comment-16898649 ] 

ASF GitHub Bot commented on AIRFLOW-5096:
-----------------------------------------

MeiK2333 commented on pull request #5709: [AIRFLOW-5096] use modification time replace last loaded time, reduce database insert
URL: https://github.com/apache/airflow/pull/5709
 
 
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   ### Description
   
   - [x] Here are some details about my PR, including screenshots of any UI changes:
   
   After the scheduler has the --do_pickle option turned on, the scheduler will insert all the file pickles into the database each time it scans the file, which will cause the database to swell rapidly.
   
   In my opinion, the main reason is because the hash function that determines whether the dag is the same as the pickle version uses the last_loaded field, which changes every time it is read instead of modified. Therefore, airflow inserts a large amount of unchanging data into the database.
   
   I created a commit in which the last modified time of the file was used instead of last_loaded as the hash field, which works fine on my computer. Please let me know if you have a better way.
   
   English is not my native language; please excuse typing errors.
   
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   This is an enhancement to existing features, I don't think there is no need for additional testing.
   
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   ### Code Quality
   
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> reduce the number of times the pickle is inserted into the database by modifying the hash field of Dag
> ------------------------------------------------------------------------------------------------------
>
>                 Key: AIRFLOW-5096
>                 URL: https://issues.apache.org/jira/browse/AIRFLOW-5096
>             Project: Apache Airflow
>          Issue Type: Improvement
>          Components: DAG
>    Affects Versions: 1.10.3
>            Reporter: MeiK
>            Assignee: MeiK
>            Priority: Minor
>
> After the scheduler has the --do_pickle option turned on, the scheduler will insert all the file pickles into the database each time it scans the file, which will cause the database to swell rapidly.
> In my opinion, the main reason is because the hash function that determines whether the dag is the same as the pickle version uses the last_loaded field, which changes every time it is read instead of modified. Therefore, airflow inserts a large amount of unchanging data into the database.
> I created a commit in which the last modified time of the file was used instead of last_loaded as the hash field, which works fine on my computer. Please let me know if you have a better way.
> English is not my native language; please excuse typing errors.



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