diff --git a/easy_profiler_core/outstream.h b/easy_profiler_core/outstream.h
index 6ffc8e7..a1272cd 100644
--- a/easy_profiler_core/outstream.h
+++ b/easy_profiler_core/outstream.h
@@ -60,6 +60,11 @@ namespace profiler {
             m_stream.write((const char*)&_data, sizeof(T));
         }
 
+        ::std::stringstream& stream()
+        {
+            return m_stream;
+        }
+
         const ::std::stringstream& stream() const
         {
             return m_stream;
diff --git a/easy_profiler_core/profile_manager.cpp b/easy_profiler_core/profile_manager.cpp
index c80d304..d965eda 100644
--- a/easy_profiler_core/profile_manager.cpp
+++ b/easy_profiler_core/profile_manager.cpp
@@ -1009,11 +1009,22 @@ uint32_t ProfileManager::dumpBlocksToStream(profiler::OStream& _outputStream, bo
 
 uint32_t ProfileManager::dumpBlocksToFile(const char* _filename)
 {
+    std::ofstream outputFile(_filename, std::fstream::binary);
+    if (!outputFile.is_open())
+        return 0;
+
     profiler::OStream outputStream;
+
+    // Replace outputStream buffer to outputFile buffer to avoid redundant copying
+    typedef ::std::basic_iostream<std::stringstream::char_type, std::stringstream::traits_type> stringstream_parent;
+    stringstream_parent& s = outputStream.stream();
+    auto oldbuf = s.rdbuf(outputFile.rdbuf());
+
+    // Write data directly to file
     const auto blocksNumber = dumpBlocksToStream(outputStream, true);
 
-    std::ofstream of(_filename, std::fstream::binary);
-    of << outputStream.stream().str();
+    // Restore old outputStream buffer to avoid possible second memory free on stringstream destructor
+    s.rdbuf(oldbuf);
 
     return blocksNumber;
 }
diff --git a/easy_profiler_core/reader.cpp b/easy_profiler_core/reader.cpp
index fbd1aa9..5da363c 100644
--- a/easy_profiler_core/reader.cpp
+++ b/easy_profiler_core/reader.cpp
@@ -372,12 +372,16 @@ extern "C" {
 
         ::std::stringstream str;
 
+        // Replace str buffer to inFile buffer to avoid redundant copying
         typedef ::std::basic_iostream<::std::stringstream::char_type, ::std::stringstream::traits_type> stringstream_parent;
         stringstream_parent& s = str;
         auto oldbuf = s.rdbuf(inFile.rdbuf());
         
+        // Read data from file
         auto result = fillTreesFromStream(progress, str, serialized_blocks, serialized_descriptors, descriptors, blocks,
                                           threaded_trees, total_descriptors_number, gather_statistics, _log);
+
+        // Restore old str buffer to avoid possible second memory free on stringstream destructor
         s.rdbuf(oldbuf);
 
         return result;