MINOR: Updated configuration docs with RocksDBConfigSetter#close

docs/streams/developer-guide/config-streams.html

@@ -684,19 +684,32 @@ <h4><a class="toc-backref" href="#id18">Default Values</a><a class="headerlink"
               <p>Here is an example that adjusts the memory size consumed by RocksDB.</p>
               <div class="highlight-java"><div class="highlight"><pre><span></span>    <span class="kd">public</span> <span class="kd">static</span> <span class="kd">class</span> <span class="nc">CustomRocksDBConfig</span> <span class="kd">implements</span> <span class="n">RocksDBConfigSetter</span> <span class="o">{</span>
 
+         <span class="c1">// These objects should be member variables so they can be closed in RocksDBConfigSetter#close.</span>
+       <span class="kd">private</span> <span class="n">org.rocksdb.Cache</span> <span class="n">cache</span> <span class="o">=</span> <span class="k">new</span> <span class="n">org</span><span class="o">.</span><span class="na">rocksdb</span><span class="o">.</span><span class="na">LRUCache</span><span class="o">(</span><span class="mi">16</span> <span class="o">*</span> <span class="mi">1024L</span> <span class="o">*</span> <span class="mi">1024L</span><span class="o">);</span>
+       <span class="kd">private</span> <span class="n">org.rocksdb.Filter</span> <span class="n">filter</span> <span class="o">=</span> <span class="k">new</span> <span class="n">org</span><span class="o">.</span><span class="na">rocksdb</span><span class="o">.</span><span class="na">BloomFilter</span><span class="o">();</span>
+
        <span class="nd">@Override</span>
        <span class="kd">public</span> <span class="kt">void</span> <span class="nf">setConfig</span><span class="o">(</span><span class="kd">final</span> <span class="n">String</span> <span class="n">storeName</span><span class="o">,</span> <span class="kd">final</span> <span class="n">Options</span> <span class="n">options</span><span class="o">,</span> <span class="kd">final</span> <span class="n">Map</span><span class="o">&lt;</span><span class="n">String</span><span class="o">,</span> <span class="n">Object</span><span class="o">&gt;</span> <span class="n">configs</span><span class="o">)</span> <span class="o">{</span>
          <span class="c1">// See #1 below.</span>
          <span class="n">BlockBasedTableConfig</span> <span class="n">tableConfig</span> <span class="o">=</span> <span class="k">new</span> <span class="n">org</span><span class="o">.</span><span class="na">rocksdb</span><span class="o">.</span><span class="na">BlockBasedTableConfig</span><span class="o">();</span>
-         <span class="n">tableConfig</span><span class="o">.</span><span class="na">setBlockCacheSize</span><span class="o">(</span><span class="mi">16</span> <span class="o">*</span> <span class="mi">1024</span> <span class="o">*</span> <span class="mi">1024L</span><span class="o">);</span>
+         <span class="n">tableConfig</span><span class="o">.</span><span class="na">setBlockCache</span><span class="o">(</span><span class="mi">cache</span></span><span class="o">);</span>
          <span class="c1">// See #2 below.</span>
          <span class="n">tableConfig</span><span class="o">.</span><span class="na">setBlockSize</span><span class="o">(</span><span class="mi">16</span> <span class="o">*</span> <span class="mi">1024L</span><span class="o">);</span>
          <span class="c1">// See #3 below.</span>
          <span class="n">tableConfig</span><span class="o">.</span><span class="na">setCacheIndexAndFilterBlocks</span><span class="o">(</span><span class="kc">true</span><span class="o">);</span>
+       <span class="c1">// See #4 below.</span>
+         <span class="n">tableConfig</span><span class="o">.</span><span class="na">setFilter</span><span class="o">(</span><span class="kc">filter</span><span class="o">);</span>
          <span class="n">options</span><span class="o">.</span><span class="na">setTableFormatConfig</span><span class="o">(</span><span class="n">tableConfig</span><span class="o">);</span>
-         <span class="c1">// See #4 below.</span>
+         <span class="c1">// See #5 below.</span>
          <span class="n">options</span><span class="o">.</span><span class="na">setMaxWriteBufferNumber</span><span class="o">(</span><span class="mi">2</span><span class="o">);</span>
        <span class="o">}</span>
+
+       <span class="nd">@Override</span>
+       <span class="kd">public</span> <span class="kt">void</span> <span class="nf">close</span><span class="o">(</span><span class="kd">final</span> <span class="n">String</span> <span class="n">storeName</span><span class="o">,</span> <span class="kd">final</span> <span class="n">Options</span> <span class="n">options</span><span class="o">)</span> <span class="o">{</span>
+         <span class="c1">// See #6 below.</span>
+         <span class="n">cache</span><span class="o">.</span><span class="na">close</span><span class="o">();</span>
+         <span class="n">filter</span><span class="o">.</span><span class="na">close</span><span class="o">();</span>
+       <span class="o">}</span>
     <span class="o">}</span>
 
 <span class="n">Properties</span> <span class="n">streamsSettings</span> <span class="o">=</span> <span class="k">new</span> <span class="n">Properties</span><span class="o">();</span>
@@ -706,10 +719,12 @@ <h4><a class="toc-backref" href="#id18">Default Values</a><a class="headerlink"
               <dl class="docutils">
                 <dt>Notes for example:</dt>
                 <dd><ol class="first last arabic simple">
-                  <li><code class="docutils literal"><span class="pre">BlockBasedTableConfig</span> <span class="pre">tableConfig</span> <span class="pre">=</span> <span class="pre">new</span> <span class="pre">org.rocksdb.BlockBasedTableConfig();</span></code> Reduce block cache size from the default, shown <a class="reference external" href="https://github.com/apache/kafka/blob/1.0/streams/src/main/java/org/apache/kafka/streams/state/internals/RocksDBStore.java#L81">here</a>,  as the total number of store RocksDB databases is partitions (40) * segments (3) = 120.</li>
-                  <li><code class="docutils literal"><span class="pre">tableConfig.setBlockSize(16</span> <span class="pre">*</span> <span class="pre">1024L);</span></code> Modify the default <a class="reference external" href="https://github.com/apache/kafka/blob/1.0/streams/src/main/java/org/apache/kafka/streams/state/internals/RocksDBStore.java#L82">block size</a> per these instructions from the <a class="reference external" href="https://github.com/facebook/rocksdb/wiki/Memory-usage-in-RocksDB#indexes-and-filter-blocks">RocksDB GitHub</a>.</li>
+                  <li><code class="docutils literal"><span class="pre">BlockBasedTableConfig</span> <span class="pre">tableConfig</span> <span class="pre">=</span> <span class="pre">new</span> <span class="pre">org.rocksdb.BlockBasedTableConfig();</span></code> Reduce block cache size from the default, shown <a class="reference external" href="https://github.com/apache/kafka/blob/2.3/streams/src/main/java/org/apache/kafka/streams/state/internals/RocksDBStore.java#L78">here</a>,  as the total number of store RocksDB databases is partitions (40) * segments (3) = 120.</li>
+                  <li><code class="docutils literal"><span class="pre">tableConfig.setBlockSize(16</span> <span class="pre">*</span> <span class="pre">1024L);</span></code> Modify the default <a class="reference external" href="https://github.com/apache/kafka/blob/2.3/streams/src/main/java/org/apache/kafka/streams/state/internals/RocksDBStore.java#L79">block size</a> per these instructions from the <a class="reference external" href="https://github.com/facebook/rocksdb/wiki/Memory-usage-in-RocksDB#indexes-and-filter-blocks">RocksDB GitHub</a>.</li>
                   <li><code class="docutils literal"><span class="pre">tableConfig.setCacheIndexAndFilterBlocks(true);</span></code> Do not let the index and filter blocks grow unbounded. For more information, see the <a class="reference external" href="https://github.com/facebook/rocksdb/wiki/Block-Cache#caching-index-and-filter-blocks">RocksDB GitHub</a>.</li>
+                  <li><code class="docutils literal"><span class="pre">tableConfig.setFilter(filter);</span></code> Creating/setting a new BlockBasedTableConfig overwrites the BloomFilter Streams uses by default. This is an important optimization and you should consider (re)setting it if you construct your own tableConfig. See  <a class="reference external" href="https://github.com/facebook/rocksdb/wiki/RocksDB-Bloom-Filter">RocksDB Bloom Filter docs</a> for details.</li>
                   <li><code class="docutils literal"><span class="pre">options.setMaxWriteBufferNumber(2);</span></code> See the advanced options in the <a class="reference external" href="https://github.com/facebook/rocksdb/blob/8dee8cad9ee6b70fd6e1a5989a8156650a70c04f/include/rocksdb/advanced_options.h#L103">RocksDB GitHub</a>.</li>
+                  <li><code class="docutils literal"><span class="pre">cache.close();</span></code> You must implement close to free the memory of any objects that extend org.rocksdb.RocksObject that you constructed. See  <a class="reference external" href="https://github.com/facebook/rocksdb/wiki/RocksJava-Basics#memory-management">RocksJava docs</a> for more details.</li>
                 </ol>
                 </dd>
               </dl>