diff --git a/src/clang_translation_unit.cc b/src/clang_translation_unit.cc
index 39f84ae5..ff9ddb9c 100644
--- a/src/clang_translation_unit.cc
+++ b/src/clang_translation_unit.cc
@@ -17,8 +17,12 @@ namespace {
 // We need to serialize requests to clang_parseTranslationUnit2FullArgv and
 // clang_reparseTranslationUnit. See
 // https://github.com/jacobdufault/cquery/issues/43#issuecomment-347614504.
-std::mutex g_parse_translation_unit_mutex;
-std::mutex g_reparse_translation_unit_mutex;
+//
+// NOTE: This is disabled because it effectively serializes indexing, as a huge
+// chunk of indexing time is spent inside of these functions.
+//
+// std::mutex g_parse_translation_unit_mutex;
+// std::mutex g_reparse_translation_unit_mutex;
 
 void EmitDiagnostics(std::string path, CXTranslationUnit tu) {
   std::string output = "Fatal errors while trying to parse " + path + "\n";
@@ -86,7 +90,7 @@ std::unique_ptr<ClangTranslationUnit> ClangTranslationUnit::Create(
   CXTranslationUnit cx_tu;
   CXErrorCode error_code;
   {
-    std::lock_guard<std::mutex> lock(g_parse_translation_unit_mutex);
+    // std::lock_guard<std::mutex> lock(g_parse_translation_unit_mutex);
     error_code = clang_parseTranslationUnit2FullArgv(
         index->cx_index, filepath.c_str(), args.data(), (int)args.size(),
         unsaved_files.data(), (unsigned)unsaved_files.size(), flags, &cx_tu);
@@ -125,7 +129,7 @@ std::unique_ptr<ClangTranslationUnit> ClangTranslationUnit::Reparse(
     std::vector<CXUnsavedFile>& unsaved) {
   int error_code;
   {
-    std::lock_guard<std::mutex> lock(g_reparse_translation_unit_mutex);
+    // std::lock_guard<std::mutex> lock(g_reparse_translation_unit_mutex);
     error_code = clang_reparseTranslationUnit(
         tu->cx_tu, (unsigned)unsaved.size(), unsaved.data(),
         clang_defaultReparseOptions(tu->cx_tu));