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+<html>
+    <body>
+        <h2>Memcache EntityStore CachePool.</h2>
+        <p>Memcache has no namespace support. In addition to that, the protocol disallow key listing.</p>
+        <p>The CachePool contract is to drop a cache once all of its references have been returned.</p>
+        <p>Therefore, all keys are prefixed, that way;</p>
+        <pre>cacheId.cacheInstanceId.key</pre>
+        <ul>
+            <li><code>cacheId</code> is the identity of the requested cache</li>
+            <li><code>cacheInstanceId</code> is an autogenerated cache instance identifier</li>
+            <li><code>key</code> is the original key</li>
+        </ul>
+        <p>
+            In other words and for a given <code>cacheId</code>, once all references of the Cache are returned to the
+            CachePool, the next <code>fetchCache(..)</code> invocation will generate a new Cache instance identifier and
+            hence use different prefixed keys.
+        </p>
+        <p>
+            All this allow the Memcache EntityStore CachePool to conform to the CachePool contract despite limitations
+            of the Memcache protocol.
+        </p>
+    </body>
+</html>
