improved buffering. (#171)

src/dftracer/df_logger.h

@@ -96,13 +96,17 @@ class DFTLogger {
 
   inline void enter_event() {
     index++;
-    level++;
-    index_stack.push_back(index.load());
+    if (include_metadata) {
+      level++;
+      index_stack.push_back(index.load());
+    }
   }
 
   inline void exit_event() {
-    level--;
-    index_stack.pop_back();
+    if (include_metadata) {
+      level--;
+      index_stack.pop_back();
+    }
   }
 
   inline TimeResolution get_time() {
@@ -121,6 +125,10 @@ class DFTLogger {
     if (dftracer_tid) {
       tid = df_gettid() + this->process_id;
     }
+    int local_index;
+    if (!include_metadata) {
+      local_index = index.load();
+    }
     if (metadata != nullptr) {
       metadata->insert_or_assign("level", level);
       int parent_index_value = -1;
@@ -152,8 +160,15 @@ class DFTLogger {
 #endif
 
     if (this->writer != nullptr) {
-      this->writer->log(index_stack[level - 1], event_name, category,
-                        start_time, duration, metadata, this->process_id, tid);
+      if (include_metadata) {
+        this->writer->log(index_stack[level - 1], event_name, category,
+                          start_time, duration, metadata, this->process_id,
+                          tid);
+      } else {
+        this->writer->log(local_index, event_name, category, start_time,
+                          duration, metadata, this->process_id, tid);
+      }
+
       has_entry = true;
     } else {
       DFTRACER_LOG_ERROR("DFTLogger.log writer not initialized", "");

src/dftracer/writer/chrome_writer.cpp

@@ -30,7 +30,7 @@ void dftracer::ChromeWriter::initialize(char *filename, bool throw_error) {
       DFTRACER_LOG_ERROR("unable to create log file %s",
                          filename);  // GCOVR_EXCL_LINE
     } else {
-      setvbuf(fh, NULL, _IOLBF, MAX_LINE_SIZE);
+      setvbuf(fh, NULL, _IOFBF, MAX_BUFFER);
       DFTRACER_LOG_INFO("created log file %s", filename);
     }
   }
@@ -58,6 +58,9 @@ void dftracer::ChromeWriter::finalize(bool has_entry) {
   DFTRACER_LOG_DEBUG("ChromeWriter.finalize", "");
   if (fh != nullptr) {
     DFTRACER_LOG_INFO("Profiler finalizing writer %s", filename.c_str());
+    if (current_index > 0) {
+      write_buffer_op(true);
+    }
     fflush(fh);
     int last_off = ftell(fh);
     (void)last_off;
@@ -118,11 +121,7 @@ void dftracer::ChromeWriter::finalize(bool has_entry) {
     hwloc_topology_destroy(topology);
 #endif
   }
-  {
-    if (current_index > 0) {
-      write_buffer_op(true);
-    }
-  }
+
   {
     std::unique_lock<std::shared_mutex> lock(mtx);
     if (buffer) {
@@ -140,6 +139,7 @@ void dftracer::ChromeWriter::convert_json(
     std::unordered_map<std::string, std::any> *metadata, ProcessID process_id,
     ThreadID thread_id) {
   auto previous_index = current_index;
+  (void)previous_index;
   char is_first_char[3] = "  ";
   if (!is_first_write) is_first_char[0] = '\0';
   if (include_metadata) {
@@ -220,7 +220,7 @@ void dftracer::ChromeWriter::convert_json(
       std::unique_lock<std::shared_mutex> lock(mtx);
       auto written_size = sprintf(
           buffer + current_index,
-          R"(%s{"id":%d,"name":"%s","cat":"%s","pid":%lu,"tid":%lu,"ts":%llu,"dur":%llu,"ph":"X","args":{}})",
+          R"(%s{"id":%d,"name":"%s","cat":"%s","pid":%lu,"tid":%lu,"ts":%llu,"dur":%llu,"ph":"X"})",
           is_first_char, index, event_name, category, process_id, thread_id,
           start_time, duration);
       current_index += written_size;

src/dftracer/writer/chrome_writer.h

@@ -56,24 +56,23 @@ class ChromeWriter {
 
   bool is_first_write;
   inline size_t write_buffer_op(bool force = false) {
-    if (!force && current_index > MAX_BUFFER) return 0;
+    if (!force && current_index < MAX_BUFFER) return 0;
     DFTRACER_LOG_DEBUG("ChromeWriter.write_buffer_op %s",
                        this->filename.c_str());
     size_t written_elements = 0;
-    auto previous_index = current_index;
     {
       std::unique_lock<std::shared_mutex> lock(mtx);
       flockfile(fh);
-      written_elements = fwrite(buffer, sizeof(char), current_index, fh);
+      written_elements = fwrite(buffer, current_index, sizeof(char), fh);
       funlockfile(fh);
       current_index = 0;
     }
 
-    if (written_elements != previous_index) {  // GCOVR_EXCL_START
+    if (written_elements != 1) {  // GCOVR_EXCL_START
       DFTRACER_LOG_ERROR(
-          "unable to log write for a+ written only %ld of %ld with error code "
+          "unable to log write for a+ written only %ld of %d with error code "
           "%d",
-          written_elements, previous_index, errno);
+          written_elements, 1, errno);
     }  // GCOVR_EXCL_STOP
     return written_elements;
   }