You are viewing a plain text version of this content. The canonical link for it is here.
Posted to yarn-issues@hadoop.apache.org by "MENG DING (JIRA)" <ji...@apache.org> on 2016/02/04 17:32:39 UTC
[jira] [Updated] (YARN-4671) There is no need to acquire CS lock
when completing a container
[ https://issues.apache.org/jira/browse/YARN-4671?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
MENG DING updated YARN-4671:
----------------------------
Description:
In YARN-4519, we discovered that there is no need to acquire CS lock in CS#completedContainerInternal, because:
* Access to critical section are already guarded by queue lock.
* It is not essential to guard {{schedulerHealth}} with cs lock in completedContainerInternal. All maps in schedulerHealth are concurrent maps. Even if schedulerHealth is not consistent at the moment, it will be eventually consistent.
With this fix, we can truly claim that CS#allocate doesn't require CS lock.
was:
In YARN-4519, we discovered that there is no need to acquire CS lock in CS#completedContainerInternal, because:
* Access to critical section are already guaranteed by queue lock.
* It is not essential to guard {{schedulerHealth}} with cs lock. All maps in schedulerHealth are concurrent maps.
With this fix, we can truly claim that CS#allocate doesn't require CS lock.
> There is no need to acquire CS lock when completing a container
> ---------------------------------------------------------------
>
> Key: YARN-4671
> URL: https://issues.apache.org/jira/browse/YARN-4671
> Project: Hadoop YARN
> Issue Type: Improvement
> Reporter: MENG DING
> Assignee: MENG DING
>
> In YARN-4519, we discovered that there is no need to acquire CS lock in CS#completedContainerInternal, because:
> * Access to critical section are already guarded by queue lock.
> * It is not essential to guard {{schedulerHealth}} with cs lock in completedContainerInternal. All maps in schedulerHealth are concurrent maps. Even if schedulerHealth is not consistent at the moment, it will be eventually consistent.
> With this fix, we can truly claim that CS#allocate doesn't require CS lock.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)