hbase-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Ted Yu (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (HBASE-13965) Stochastic Load Balancer JMX Metrics
Date Sun, 12 Jul 2015 00:10:04 GMT

    [ https://issues.apache.org/jira/browse/HBASE-13965?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14623634#comment-14623634

Ted Yu commented on HBASE-13965:

+  /** Config for balancing the cluster by each table */
'by each table' -> 'by table'
+  /** The name of the combined table when bytable is off*/
'combined table' -> 'combined tables'
+  // Use Most Recent Used(MRU) cache
'Most Recent' -> 'Most Recently'
+    synchronized (stochasticCosts) {
+      if (stochasticCosts != null) {
Looks like the null check is not needed.
+  private void updateStochasticCosts(TableName tableName, Double overall, Double[] subCosts)
Should we do early return if the table is system table ?
+          //TODO: should hbase:mespace be passed in by HMaster?
Can the above TODO be dropped ?
+      ((MetricsStochasticBalancer) metricsBalancer).updateStochasticCost(tableName.getNameAsString(),
+        "Overall cost", overall);
Since metricsBalancer would be cast in the loop that follows, you can use local variable of
type MetricsStochasticBalancer to save the casts in the loop.
+    if (null == tableName)
+      return;
nit: move return on the same line as if statement to save a pair of curly braces.

> 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-v3.patch, HBASE-13965-v4.patch, HBASE-13965-v5.patch,
HBASE-13965-v6.patch, HBASE-13965-v7.patch, HBASE-13965_v2.patch, 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

View raw message