HBASE-18737 Display configured max size of cache on RS UI

Signed-off-by: tedyu <yuzhihong@gmail.com>

hbase-external-blockcache/src/main/java/org/apache/hadoop/hbase/io/hfile/MemcachedBlockCache.java

@@ -194,6 +194,11 @@ public class MemcachedBlockCache implements BlockCache {
     return 0;
   }
 
+  @Override
+  public long getMaxSize() {
+    return 0;
+  }
+
   @Override
   public long getFreeSize() {
     return 0;

hbase-server/src/main/jamon/org/apache/hadoop/hbase/tmpl/regionserver/BlockCacheTmpl.jamon

@@ -326,25 +326,30 @@ are combined counts. Request count is sum of hits and misses.</p>
     </tr>
 </%if>
     <tr>
-        <td>Count</td>
+        <td>Cache Size Limit</td>
+        <td><% TraditionalBinaryPrefix.long2String(bc.getMaxSize(), "B", 1) %></td>
+        <td>Max size of cache</td>
+    </tr>
+    <tr>
+        <td>Block Count</td>
         <td><% String.format("%,d", bc.getBlockCount()) %></td>
         <td>Count of Blocks</td>
     </tr>
 <%if !bucketCache %>
     <tr>
-        <td>Count</td>
+        <td>Data Block Count</td>
         <td><% String.format("%,d", bc.getDataBlockCount()) %></td>
         <td>Count of DATA Blocks</td>
     </tr>
 </%if>
     <tr>
-        <td>Size</td>
+        <td>Size of Blocks</td>
         <td><% TraditionalBinaryPrefix.long2String(bc.getCurrentSize(), "B", 1) %></td>
         <td>Size of Blocks</td>
     </tr>
 <%if !bucketCache %>
     <tr>
-        <td>Size</td>
+        <td>Size of Data Blocks</td>
         <td><% TraditionalBinaryPrefix.long2String(bc.getCurrentDataSize(), "B", 1) %></td>
         <td>Size of DATA Blocks</td>
     </tr>

hbase-server/src/main/jamon/org/apache/hadoop/hbase/tmpl/regionserver/RSStatusTmpl.jamon

@@ -109,12 +109,12 @@ org.apache.hadoop.hbase.zookeeper.MasterAddressTracker;
     </section>
 
     <section>
-    <& ../common/TaskMonitorTmpl; filter = filter &>
+    <h2>Block Cache</h2>
+    <& BlockCacheTmpl; cacheConfig = regionServer.getCacheConfig(); config = regionServer.getConfiguration() &>
     </section>
 
     <section>
-    <h2>Block Cache</h2>
-    <& BlockCacheTmpl; cacheConfig = regionServer.getCacheConfig(); config = regionServer.getConfiguration() &>
+    <& ../common/TaskMonitorTmpl; filter = filter &>
     </section>
 
     <section>

hbase-server/src/main/jamon/org/apache/hadoop/hbase/tmpl/regionserver/ServerMetricsTmpl.jamon

@@ -127,7 +127,9 @@ MetricsRegionServerWrapper mWrap;
     <td>
         <% TraditionalBinaryPrefix.long2String(DirectMemoryUtils.getDirectMemorySize(), "B", 1) %>
     </td>
-    <td><% TraditionalBinaryPrefix.long2String(mWrap.getMemstoreSize(), "B", 1) %></td>
+    <td>
+        <% TraditionalBinaryPrefix.long2String(mWrap.getMemstoreSize(), "B", 1) %>
+    </td>
 </tr>
 </table>
 </%def>

hbase-server/src/main/java/org/apache/hadoop/hbase/io/hfile/BlockCache.java

@@ -89,6 +89,12 @@ public interface BlockCache extends Iterable<CachedBlock> {
    */
   long size();
 
+  /**
+   * Returns the Max size of the block cache, in bytes.
+   * @return size of cache, in bytes
+   */
+  long getMaxSize();
+
   /**
    * Returns the free size of the block cache, in bytes.
    * @return free space in cache, in bytes

hbase-server/src/main/java/org/apache/hadoop/hbase/io/hfile/CombinedBlockCache.java

@@ -111,6 +111,11 @@ public class CombinedBlockCache implements ResizableBlockCache, HeapSize {
     return lruCache.size() + l2Cache.size();
   }
 
+  @Override
+  public long getMaxSize() {
+    return lruCache.getMaxSize() + l2Cache.getMaxSize();
+  }
+
   @Override
   public long getFreeSize() {
     return lruCache.getFreeSize() + l2Cache.getFreeSize();

hbase-server/src/main/java/org/apache/hadoop/hbase/io/hfile/LruBlockCache.java

@@ -830,6 +830,8 @@ public class LruBlockCache implements ResizableBlockCache, HeapSize {
    * Get the maximum size of this cache.
    * @return max size in bytes
    */
+
+  @Override
   public long getMaxSize() {
     return this.maxSize;
   }

hbase-server/src/main/java/org/apache/hadoop/hbase/io/hfile/bucket/BucketCache.java

@@ -348,6 +348,7 @@ public class BucketCache implements BlockCache, HeapSize {
     return this.cacheEnabled;
   }
 
+  @Override
   public long getMaxSize() {
     return this.cacheCapacity;
   }

hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestHeapMemoryManager.java

@@ -585,6 +585,11 @@ public class TestHeapMemoryManager {
       return 0;
     }
 
+    @Override
+    public long getMaxSize() {
+      return 0;
+    }
+
     @Override
     public long getFreeSize() {
       return 0;