[jira] [Commented] (ZOOKEEPER-4009) Add Four-letter command to shed clients

["Li Wang (Jira)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/ZOOKEEPER-4009?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17235821#comment-17235821 ] 

Li Wang commented on ZOOKEEPER-4009:
------------------------------------

Introduce 3 new 4-letter commands:
 * shed: close all client connections
 * sh25: close approximatively 1/4 of client connections
 * sh50: close approximatively half of client connections

In clusters with large number of clients, a rolling bounce (or multiple) can lead to a situation of severe connection imbalance.

In these situations, restarting clients is the only solution to rebalance the load among servers.

This change introduces server admin command that voluntarily close client connections.
Clients should be able to migrate transparently to another server, just like in case of actual disconnection or server crash.

> Add Four-letter command to shed clients
> ---------------------------------------
>
>                 Key: ZOOKEEPER-4009
>                 URL: https://issues.apache.org/jira/browse/ZOOKEEPER-4009
>             Project: ZooKeeper
>          Issue Type: New Feature
>            Reporter: Li Wang
>            Priority: Major
>
> In some circumstances, it is useful to ask a server to drop part (or all) of its client connections.
> Those clients will treat this as a regular disconnection and will migrate to a different random ensemble servers.
> Use cases include
>  - Fixing client imbalance
>  - Gradually shedding all clients before taking a server down for maintenance
>  - Remove load from leader



--
This message was sent by Atlassian Jira
(v8.3.4#803005)