HBASE-14433 Set down the client executor core thread count from 256 to number of processors

hbase-client/src/main/java/org/apache/hadoop/hbase/client/ConnectionImplementation.java

@@ -370,7 +370,9 @@ class ConnectionImplementation implements ClusterConnection, Closeable {
       synchronized (this) {
         if (batchPool == null) {
           this.batchPool = getThreadPool(conf.getInt("hbase.hconnection.threads.max", 256),
-              conf.getInt("hbase.hconnection.threads.core", 256), "-shared-", null); 
+            conf.getInt("hbase.hconnection.threads.core",
+              Runtime.getRuntime().availableProcessors()),
+            "-shared-", null); 
           this.cleanupPool = true;
         }
       }
@@ -385,7 +387,7 @@ class ConnectionImplementation implements ClusterConnection, Closeable {
       maxThreads = Runtime.getRuntime().availableProcessors() * 8;
     }
     if (coreThreads == 0) {
-      coreThreads = Runtime.getRuntime().availableProcessors() * 8;
+      coreThreads = Runtime.getRuntime().availableProcessors();
     }
     long keepAliveTime = conf.getLong("hbase.hconnection.threads.keepalivetime", 60);
     BlockingQueue<Runnable> workQueue = passedWorkQueue;

hbase-client/src/test/resources/hbase-site.xml

@@ -25,4 +25,12 @@
     <name>hbase.defaults.for.version.skip</name>
     <value>true</value>
   </property>
+  <property>
+    <name>hbase.hconnection.meta.lookup.threads.core</name>
+    <value>4</value>
+  </property>
+  <property>
+    <name>hbase.hconnection.threads.keepalivetime</name>
+    <value>3</value>
+  </property>
 </configuration>

hbase-server/src/test/resources/hbase-site.xml

@@ -162,4 +162,12 @@
       Enable replay sanity checks on procedure tests.
     </description>
   </property>
+  <property>
+    <name>hbase.hconnection.meta.lookup.threads.core</name>
+    <value>4</value>
+  </property>
+  <property>
+    <name>hbase.hconnection.threads.keepalivetime</name>
+    <value>3</value>
+  </property>
 </configuration>