Add BloomFilter to levelDB

src/LevelDBStore/IO/Data/LevelDB/Native.cs

@@ -155,6 +155,9 @@ public static class Native
 
         [DllImport("libleveldb", CharSet = CharSet.Ansi, CallingConvention = CallingConvention.Cdecl)]
         public static extern void leveldb_options_set_filter_policy(IntPtr /*Options*/ options, IntPtr /*FilterPolicy*/ policy);
+
+        [DllImport("libleveldb", CharSet = CharSet.Ansi, CallingConvention = CallingConvention.Cdecl)]
+        public static extern IntPtr leveldb_filterpolicy_create_bloom(int bits_per_key);
         #endregion
 
         #region ReadOptions

src/LevelDBStore/LevelDBStore/config.json

@@ -1,4 +1,4 @@
-{
+{
   "PluginConfiguration": {
     "Path": "Data_LevelDB_{0}"
   }

src/LevelDBStore/Plugins/Storage/Store.cs

@@ -16,7 +16,7 @@ internal class Store : IStore
 
         public Store(string path)
         {
-            this.db = DB.Open(path, new Options { CreateIfMissing = true });
+            this.db = DB.Open(path, new Options { CreateIfMissing = true, FilterPolicy = Native.leveldb_filterpolicy_create_bloom(15) });
             byte[] value = db.Get(ReadOptions.Default, LHelper.CreateKey(SYS_Version));
             if (value != null && Version.TryParse(Encoding.ASCII.GetString(value), out Version version) && version >= Version.Parse("3.0.0"))
                 return;