[ 
https://issues.apache.org/jira/browse/FLINK-39423?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

Rui Fan updated FLINK-39423:
----------------------------
    Description: 
h2. Problem

All boolean config options always get the *same* value within a single test — 
either all {{true}} or all {{{}false{}}}:
{code:java}
Randomly selected true for 
execution.checkpointing.unaligned.recover-output-on-downstream.enabled
Randomly selected true for 
execution.checkpointing.unaligned.during-recovery.enabled
Randomly selected true for execution.checkpointing.cleaner.parallel-mode
Randomly selected true for 
execution.checkpointing.unaligned.interruptible-timers.enabled
Randomly selected true for execution.checkpointing.snapshot-compression
Randomly selected true for execution.checkpointing.file-merging.enabled
Randomly selected true for 
state.backend.rocksdb.use-ingest-db-restore-mode{code}
 

This reduces test coverage since many configuration combinations are never 
tested.
h2. Root Cause

[{{randomize()}}|https://github.com/apache/flink/blob/master/flink-runtime/src/test/java/org/apache/flink/runtime/testutils/PseudoRandomValueSelector.java#L128-L133]
 [1] creates a new {{java.util.Random}} with the same seed (commit hash + test 
name) for every call. Since {{new Random(seed).nextInt(2)}} is deterministic, 
all boolean options get identical results.
h2. Fix

Include the config option key in the seed so each option gets a different seed:
{code:java}
PseudoRandomValueSelector.create(
    (testName != null ? testName : "unknown") + option.key());{code}
 

{{[1] }}
[https://github.com/apache/flink/blob/master/flink-runtime/src/test/java/org/apache/flink/runtime/testutils/PseudoRandomValueSelector.java#L128-L133]

  was:
h2. Problem

All boolean config options always get the *same* value within a single test — 
either all {{true}} or all {{{}false{}}}:

{{}}
{code:java}

{code}
{{Randomly selected true for 
execution.checkpointing.unaligned.recover-output-on-downstream.enabled }}
{{Randomly selected true for 
execution.checkpointing.unaligned.during-recovery.enabled }}
{{Randomly selected true for execution.checkpointing.cleaner.parallel-mode }}
{{Randomly selected true for 
execution.checkpointing.unaligned.interruptible-timers.enabled }}
{{Randomly selected true for execution.checkpointing.snapshot-compression }}
{{Randomly selected true for execution.checkpointing.file-merging.enabled }}
{{Randomly selected true for state.backend.rocksdb.use-ingest-db-restore-mode}}

{{ }}

 

This reduces test coverage since many configuration combinations are never 
tested.
h2. Root Cause

[{{randomize()}}|https://github.com/apache/flink/blob/master/flink-runtime/src/test/java/org/apache/flink/runtime/testutils/PseudoRandomValueSelector.java#L128-L133]
 [1] creates a new {{java.util.Random}} with the same seed (commit hash + test 
name) for every call. Since {{new Random(seed).nextInt(2)}} is deterministic, 
all boolean options get identical results.
h2. Fix

Include the config option key in the seed so each option gets a different seed:

{{}}
{code:java}

{code}
{{PseudoRandomValueSelector.create(}}
{{ (testName != null ? testName : "unknown") + option.key());}}

 

{{}}

{{[1] }}
https://github.com/apache/flink/blob/master/flink-runtime/src/test/java/org/apache/flink/runtime/testutils/PseudoRandomValueSelector.java#L128-L133
{{}}


> Fix PseudoRandomValueSelector.randomize() producing identical values for all 
> boolean config options
> ---------------------------------------------------------------------------------------------------
>
>                 Key: FLINK-39423
>                 URL: https://issues.apache.org/jira/browse/FLINK-39423
>             Project: Flink
>          Issue Type: Bug
>          Components: Test Infrastructure
>            Reporter: Rui Fan
>            Assignee: Rui Fan
>            Priority: Major
>
> h2. Problem
> All boolean config options always get the *same* value within a single test — 
> either all {{true}} or all {{{}false{}}}:
> {code:java}
> Randomly selected true for 
> execution.checkpointing.unaligned.recover-output-on-downstream.enabled
> Randomly selected true for 
> execution.checkpointing.unaligned.during-recovery.enabled
> Randomly selected true for execution.checkpointing.cleaner.parallel-mode
> Randomly selected true for 
> execution.checkpointing.unaligned.interruptible-timers.enabled
> Randomly selected true for execution.checkpointing.snapshot-compression
> Randomly selected true for execution.checkpointing.file-merging.enabled
> Randomly selected true for 
> state.backend.rocksdb.use-ingest-db-restore-mode{code}
>  
> This reduces test coverage since many configuration combinations are never 
> tested.
> h2. Root Cause
> [{{randomize()}}|https://github.com/apache/flink/blob/master/flink-runtime/src/test/java/org/apache/flink/runtime/testutils/PseudoRandomValueSelector.java#L128-L133]
>  [1] creates a new {{java.util.Random}} with the same seed (commit hash + 
> test name) for every call. Since {{new Random(seed).nextInt(2)}} is 
> deterministic, all boolean options get identical results.
> h2. Fix
> Include the config option key in the seed so each option gets a different 
> seed:
> {code:java}
> PseudoRandomValueSelector.create(
>     (testName != null ? testName : "unknown") + option.key());{code}
>  
> {{[1] }}
> [https://github.com/apache/flink/blob/master/flink-runtime/src/test/java/org/apache/flink/runtime/testutils/PseudoRandomValueSelector.java#L128-L133]



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

Reply via email to