[
https://issues.apache.org/jira/browse/KAFKA-8270?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Jiangtao Liu updated KAFKA-8270:
--------------------------------
Attachment: Screen Shot 2020-04-15 at 11.02.55 AM.png
> Kafka timestamp-based retention policy is not working when Kafka client's
> time is not reliable.
> -----------------------------------------------------------------------------------------------
>
> Key: KAFKA-8270
> URL: https://issues.apache.org/jira/browse/KAFKA-8270
> Project: Kafka
> Issue Type: Bug
> Components: log, log cleaner, logging
> Affects Versions: 1.1.1
> Reporter: Jiangtao Liu
> Priority: Major
> Labels: storage
>
> What's the issue?
> {quote} # There were log segments, which can not be deleted over configured
> retention hours.{quote}
> What are impacts?
> {quote} # Log space keep in increasing and finally cause space shortage.
> # There are lots of log segment rolled with a smaller size. e.g log segment
> may be only 50mb, not the expected 1gb.
> # Kafka stream or client may experience missing data.
> # It will be a way used to attack Kafka server.{quote}
> What's workaround adopted to resolve this issue?
> {quote} # If it's already happened on your Kafka system, you will need to run
> a very tricky steps to resolve it.
> # If it has not happened on your Kafka system yet, you may need to evaluate
> whether you can switch to LogAppendTime for log.message.timestamp.type.
> {quote}
> What are the reproduce steps?
> {quote} # Make sure Kafka client and server are not hosted in the same
> machine.
> # Configure log.message.timestamp.type with *CreateTime*, not LogAppendTime.
> # Hack Kafka client's system clock time with a *future time*, e.g
> 03/04/*2025*, 3:25:52 PM
> [GMT-08:00|https://www.epochconverter.com/timezones?q=1741130752]
> # Send message from Kafka client to server.{quote}
> What kinds of things you need to have a look after message handled by Kafka
> server?
> {quote} # Check the timestamp in segment *.timeindex and record in segment
> *.log. You will see all the timestamp values in **.timeindex are messed up
> with a future time after `03/04/*2025*, 3:25:52 PM
> [GMT-08:00|https://www.epochconverter.com/timezones?q=1741130752]`. (Let's
> say 00000000035957300794.log is the log segment which first receive the test
> client's message. It will be referenced in #3)
> # You will also see the log segment will be rolled with a smaller size (e.g
> 50mb) than configured segment max size (e.g 1gb).
> # All of log segments including 00000000035957300794.* and new rolled, will
> not be deleted over retention hours.{quote}
> What's the particular logic to cause this issue?
> {quote} # private def deletableSegments(predicate: (LogSegment,
> Option[LogSegment]) =>
> Boolean)|[https://github.com/apache/kafka/blob/1.1/core/src/main/scala/kafka/log/Log.scala#L1227]]
> will always return empty deletable log segments.{color:#172b4d}
> {color}{quote}
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
