[jira] [Commented] (CLOUDSTACK-9180) Optimize concurrent VM deployment operation on same network

["ASF GitHub Bot (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/CLOUDSTACK-9180?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15059921#comment-15059921 ] 

ASF GitHub Bot commented on CLOUDSTACK-9180:
--------------------------------------------

GitHub user koushik-das opened a pull request:

    https://github.com/apache/cloudstack/pull/1251

    CLOUDSTACK-9180: Optimize concurrent VM deployment operation on same …

    …network
    
    Check if VR needs to be allocated for a given network and only acquire lock if required
    
    Refer to the bug for details.

You can merge this pull request into a Git repository by running:

    $ git pull https://github.com/koushik-das/cloudstack CLOUDSTACK-9180

Alternatively you can review and apply these changes as the patch at:

    https://github.com/apache/cloudstack/pull/1251.patch

To close this pull request, make a commit to your master/trunk branch
with (at least) the following in the commit message:

    This closes #1251
    
----
commit de8942644df26fdd97010f8eec1fddf7d97fc8ae
Author: Koushik Das <ko...@apache.org>
Date:   2015-12-16T12:23:03Z

    CLOUDSTACK-9180: Optimize concurrent VM deployment operation on same network
    Check if VR needs to be allocated for a given network and only acquire lock if required

----


> Optimize concurrent VM deployment operation on same network
> -----------------------------------------------------------
>
>                 Key: CLOUDSTACK-9180
>                 URL: https://issues.apache.org/jira/browse/CLOUDSTACK-9180
>             Project: CloudStack
>          Issue Type: Bug
>      Security Level: Public(Anyone can view this level - this is the default.) 
>          Components: Management Server
>    Affects Versions: 4.6.0
>            Reporter: Koushik Das
>            Assignee: Koushik Das
>             Fix For: 4.7.0
>
>
> During VM deployment a check is performed to see if VR exists or not. If not it is created - first an entry is allocated in DB for VR and then it is deployed. The allocation logic is placed in a lock (based on network id) so that only one thread does the allocation. But the locking is implemented in a way such that all threads wait on that lock even when VR is already allocated. The correct approach would be to check if VR is allocated or not and acquire lock only when needed.
> This issue is more frequently seen when concurrently deploying VMs in basic zone as all threads try to acquire lock using the same network id. In advanced zone operations are spread across multiple networks and so less frequent.
> Refer to findOrDeployVirtualRouter() in RouterDeploymentDefinition.java.



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