Add Documentation

README.md

@@ -2,7 +2,21 @@
 
 Based on LSM tree-structured database with up to 100,000 data writes per second.
 
-## Create DB
+# introduce
+1. Developed using the LSM architecture
+2. Serialization and deserialization of data in the form of ProtoBuf
+3. Use direct memory to reduce one copy of the IO process
+4. Memory structure support Bloom filters, jump tables 
+5. Multi-threaded read/write support
+6. Use of buffer pools to increase read efficiency
+7. Supports Size-tire compression and Level compression
+8. Support repeatable reads, read committed isolation level.
+9. Optimize SSTable, Key and Value separation.
+10. Write metadata twice to prevent complete data loss
+11. Support for version snapshots
+12. Optimistic locking and pessimistic locking transactions. 
+
+## example
 
 ```
 
@@ -20,7 +34,7 @@ Based on LSM tree-structured database with up to 100,000 data writes per second.
     columnFamilyHandle=openDB.getColumnFamilyHandle("luoluoyuyu").date;
 ```
 
-benchmark
+#benchmark
 ```
 Benchmark                     Mode  Cnt       Score   Error  Units
 OpenDBBenchmark.addKeyValue  thrpt       134061.544          ops/s