[
https://issues.apache.org/jira/browse/HBASE-13965?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14609007#comment-14609007
]
stack commented on HBASE-13965:
-------------------------------
Thank you for the design and patch overview. Helps.
The changes in your patch to hbase-env.sh are probably not intended. Ditto
hbase-site.xml... and others.
Add license to new classes (see adjacent classes for how), javadoc on
Interfaces especially (no need of public qualifiers when an Interface), and see
annotations in accompanying classes and apply as appropriate here (mark them
private I'd say).
I wouldn't even bother offering DEFAULT vs STOCHASTIC. No one runs any balancer
but stochastic (Besides default is the Stochastic). Remove the choice.
Otherwise, patch looking good. Suggest you past example of what it looks like
when it is working.
FYI [~eclark]
> Stochastic Load Balancer JMX Metrics
> ------------------------------------
>
> Key: HBASE-13965
> URL: https://issues.apache.org/jira/browse/HBASE-13965
> Project: HBase
> Issue Type: Improvement
> Components: Balancer, metrics
> Reporter: Lei Chen
> Assignee: Lei Chen
> Attachments: HBase-13965-v1.patch,
> stochasticloadbalancerclasses_v2.png
>
>
> Today’s default HBase load balancer (the Stochastic load balancer) is cost
> function based. The cost function weights are tunable but no visibility into
> those cost function results is directly provided.
> A driving example is a cluster we have been tuning which has skewed rack size
> (one rack has half the nodes of the other few racks). We are tuning the
> cluster for uniform response time from all region servers with the ability to
> tolerate a rack failure. Balancing LocalityCost, RegionReplicaRack Cost and
> RegionCountSkew Cost is difficult without a way to attribute each cost
> function’s contribution to overall cost.
> What this jira proposes is to provide visibility via JMX into each cost
> function of the stochastic load balancer, as well as the overall cost of the
> balancing plan.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
