[ 
https://issues.apache.org/jira/browse/KAFKA-3788?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15321014#comment-15321014
 ] 

Bharat Viswanadham commented on KAFKA-3788:
-------------------------------------------

Can I take this task, to work on it?

> Potential message lost when switching to new segment
> ----------------------------------------------------
>
>                 Key: KAFKA-3788
>                 URL: https://issues.apache.org/jira/browse/KAFKA-3788
>             Project: Kafka
>          Issue Type: Bug
>          Components: log
>    Affects Versions: 0.9.0.0, 0.9.0.1, 0.10.0.0
>            Reporter: Arkadiusz Firus
>            Assignee: Jay Kreps
>            Priority: Minor
>              Labels: easyfix
>   Original Estimate: 1h
>  Remaining Estimate: 1h
>
> If a new segment is needed method roll() from class kafka.log.Log is invoked. 
> It prepares new segment and schedules _asynchronous_ flush of the previous 
> segment.
> Asynchronous call can lead to a problematic situation. As far as I know 
> neither Linux nor Windows guarantees that the order of files persisted to 
> disk will be the same as the order of writes to files. This means that 
> records from the new segment can be flushed before the old ones which in case 
> of power outage can lead to gaps between records.
> Changing asynchronous invocation to synchronous one will solve the problem 
> because we have guarantee that all records from the previous segment will be 
> persisted to hard drive before we write any record to the new segment.
> I am guessing that asynchronous invocation was chosen to increase performance 
> but switching between segments is not so often. So it is not a big gain.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Reply via email to