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https://issues.apache.org/jira/browse/BEAM-10824?focusedWorklogId=477604&page=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-477604
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ASF GitHub Bot logged work on BEAM-10824:
-----------------------------------------
Author: ASF GitHub Bot
Created on: 02/Sep/20 04:33
Start Date: 02/Sep/20 04:33
Worklog Time Spent: 10m
Work Description: monicadsong commented on pull request #12756:
URL: https://github.com/apache/beam/pull/12756#issuecomment-685288813
R: @tvalentyn
Went with hashlib instead.
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Issue Time Tracking
-------------------
Worklog Id: (was: 477604)
Remaining Estimate: 22h 20m (was: 22.5h)
Time Spent: 1h 40m (was: 1.5h)
> Hash in stats.ApproximateUniqueCombineFn NON-deterministic
> ----------------------------------------------------------
>
> Key: BEAM-10824
> URL: https://issues.apache.org/jira/browse/BEAM-10824
> Project: Beam
> Issue Type: Bug
> Components: beam-model
> Reporter: Monica Song
> Priority: P1
> Labels: hash
> Original Estimate: 24h
> Time Spent: 1h 40m
> Remaining Estimate: 22h 20m
>
> The python hash() function is non-deterministic. As a result, different
> workers will map identical values to different hashes. This leads to
> overestimation of the number of unique values (by several magnitudes, in my
> experience x1000) in a distributed processing model.
> [https://github.com/apache/beam/blob/master/sdks/python/apache_beam/transforms/stats.py#L218]
>
>
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