Update rocksdb.go (#218)

Author: faddat

rocksdb.go

@@ -37,6 +37,8 @@ func NewRocksDB(name string, dir string) (*RocksDB, error) {
 
 	opts := gorocksdb.NewDefaultOptions()
 	opts.SetBlockBasedTableFactory(bbto)
+	// SetMaxOpenFiles to 4096 seems to provide a reliable performance boost
+	opts.SetMaxOpenFiles(4096)
 	opts.SetCreateIfMissing(true)
 	opts.IncreaseParallelism(runtime.NumCPU())
 	// 1.5GB maximum memory use for writebuffer.