kafka-jira mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Bill Bejeck (JIRA)" <j...@apache.org>
Subject [jira] [Assigned] (KAFKA-5932) Avoid call fetchPrevious in FlushListeners
Date Tue, 19 Sep 2017 18:12:00 GMT

     [ https://issues.apache.org/jira/browse/KAFKA-5932?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]

Bill Bejeck reassigned KAFKA-5932:
----------------------------------

    Assignee: Bill Bejeck

> Avoid call fetchPrevious in FlushListeners
> ------------------------------------------
>
>                 Key: KAFKA-5932
>                 URL: https://issues.apache.org/jira/browse/KAFKA-5932
>             Project: Kafka
>          Issue Type: Improvement
>          Components: streams
>            Reporter: Guozhang Wang
>            Assignee: Bill Bejeck
>
> When caching is turned on for a window or session store, upon {{store.put()}} the cache
may gets flushed, trigger the dirty flush listener calling {{maybeForward()}}, which calls
{{fetchPrevious()}}.
> Unfortunately {{fetchPrevious()}} could be a very expensive call to make, and sometimes
are not necessary:
> 1. When {{KStreamWindowAggregate.process()}} already gets the previous value when aggregating,
so we could passing the old value through the tuple forwarder without calling fetchPrevious
again.
> 2. When we know that {{sendOldValues}} flag is turned off.



--
This message was sent by Atlassian JIRA
(v6.4.14#64029)

Mime
View raw message