[sample-generation] Speed up event merging step

Speed up event merging step

See merge request abrusamo/pftruth-standalone!6

data/makeSamples.py

@@ -59,6 +59,9 @@ def makeEvent(config_file, event=None):
 def makeEventWrapper(args):
     makeEvent(args[0], args[1])
 
+def mergeCSVFilesWrapper(args):
+    mergeCSVFiles(args)
+
 if __name__ == '__main__':
 
     parser = argparse.ArgumentParser(description='Generate samples')
@@ -103,8 +106,10 @@ if __name__ == '__main__':
     labels = [re.sub(pattern, '', csv_file) for csv_file in csv_files]
     labels = list(set(labels))
 
+    with concurrent.futures.ProcessPoolExecutor(len(labels)) as executor:
         for label in labels:
-        mergeCSVFiles(label, tmp_dir, csv_dir)
+            executor.submit(mergeCSVFilesWrapper, label)
+
     stop = time.time()
     mergeDelta = stop - start