[
https://issues.apache.org/jira/browse/HBASE-5959?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13274041#comment-13274041
]
Zhihong Yu commented on HBASE-5959:
-----------------------------------
For computeTableSkewLoadCost(), normally we use region count (per table) for
region servers to judge skew.
I feel the skew in table count is not a good indicator.
{code}
+ * @return Cost of imbalance in table.
{code}
'table' -> 'tables'
{code}
+ for (Entry<ServerName, List<HRegionInfo>> entry : clusterState.entrySet())
{
+ Set<String> tablesOnRegionServer = new HashSet<String>();
{code}
We can clear the HashSet after the following line in the loop (instead of
creating HashSet every iteration):
{code}
+ tablesPerServer.add(new Double(tablesOnRegionServer.size()));
{code}
Math.abs() is not needed in the following:
{code}
+ skewCost += Math.abs(numTables - count.doubleValue());
{code}
For computeDataLocalityCost():
{code}
+ // If we can't find where the data is getTopBlock returns null.
+ // so count that as being the best possible.
+ if (dataOnServers == null) {
{code}
I think worst should be assumed if block locations cannot be retrieved.
I asked the coefficients of various costs to be configurable. This is because
users tend to give high priority to locality cost component.
BalancerTestBase.java is missing license.
{code}
+ * Class used to be the base of unit tests on load balancers. It gives helper
{code}
'Class used to be the base' -> 'Base class'.
assertClusterAsBalanced() should be package-private.
For reconcile(),
{code}
+ * This assumes the RegionPlan HSI instances are the same ones in the map, so
+ * actually no need to even pass in the map, but I think it's clearer.
{code}
Please expand HSI to full class name. The two parameters are both Lists. Where
is the map ? I think it is Map<ServerName, ServerAndLoad> map.
Please describe what this method does.
> Add other load balancers
> ------------------------
>
> Key: HBASE-5959
> URL: https://issues.apache.org/jira/browse/HBASE-5959
> Project: HBase
> Issue Type: New Feature
> Components: master
> Affects Versions: 0.96.0
> Reporter: Elliott Clark
> Assignee: Elliott Clark
> Attachments: HBASE-5959-0.patch, HBASE-5959-1.patch,
> HBASE-5959-2.patch, HBASE-5959-3.patch
>
>
> Now that balancers are pluggable we should give some options.b
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators:
https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa
For more information on JIRA, see: http://www.atlassian.com/software/jira
