They are similar but not quite the same. The JobManager was responsible
for managing multiple jobs, whereas the JobMaster only manages a single
job. The responsibility for managing multiple jobs (==JobMasters) and
accepting job submissions was moved into the Dispatcher.
On 31/01/2020 09:39, Lu Weizheng wrote:
Hi Yun, thank you so much for your reply!
I have briefly read all links in your reply. So the JobManager.scala
was removed and JobMaster was added and functions what JobManager did
before?
Best Regards
Weizheng
------------------------------------------------------------------------
*发件人:* Yun Tang <myas...@live.com>
*发送时间:* 2020年1月31日 15:20
*收件人:* Lu Weizheng <luweizhen...@hotmail.com>; user@flink.apache.org
<user@flink.apache.org>
*主题:* Re: Difference between JobManager and JobMaster
Hi Wizheng
FLIP-6 [1] introduce a new implementation of master component in Flink
cluster with name of `JobMaster.java`[2], you can find previous
implementation in Flink-1.7 as `JobManager.scala` [3]. However, we
would still call the master component as 'JobManager' though its
implementation name has been changed.
If you want to know more details, please read FLIP-6 and its JIRA
issue FLINK-4319 [4].
[1]
https://cwiki.apache.org/confluence/pages/viewpage.action?pageId=65147077
[2]
https://github.com/apache/flink/blob/release-1.10/flink-runtime/src/main/java/org/apache/flink/runtime/jobmaster/JobMaster.java
[3]
https://github.com/apache/flink/blob/release-1.7/flink-runtime/src/main/scala/org/apache/flink/runtime/jobmanager/JobManager.scala
[4] https://issues.apache.org/jira/browse/FLINK-4319
<https://issues.apache.org/jira/browse/FLINK-4319>
Best
Yun Tang
------------------------------------------------------------------------
*From:* Lu Weizheng <luweizhen...@hotmail.com>
*Sent:* Friday, January 31, 2020 10:25
*To:* user@flink.apache.org <user@flink.apache.org>
*Subject:* Difference between JobManager and JobMaster
Hi all,
Recently I am reading source code of Flink. There are both JobManager
and JobMaster in flink-runtime project. And JobManagerRunner interface
says it is a runner which executes a JobMaster. So how to distinguish
the two concepts? Is JobMaster a subset of JobManager? Or JobMaster is
a new version which is going to replace the function of JobManager? Or
the two roles are different?
Thank you!
Weizheng
