diff --git a/tools/profiling/microbenchmarks/bm_diff.py b/tools/profiling/microbenchmarks/bm_diff.py
index d6119332a7730506eee907008f854d2ae48a8f87..6f39738f59480ebd135b0991b39f41e9c4eaf7f5 100755
--- a/tools/profiling/microbenchmarks/bm_diff.py
+++ b/tools/profiling/microbenchmarks/bm_diff.py
@@ -185,6 +185,9 @@ class Benchmark:
       old_mdn = median(old)
       delta = new_mdn - old_mdn
       ratio = changed_ratio(new_mdn, old_mdn)
+      print 'new=%r old=%r new_mdn=%f old_mdn=%f delta=%f ratio=%f p=%f' % (
+      new, old, new_mdn, old_mdn, delta, ratio, p
+      )
       if p < args.p_threshold and abs(delta) > _INTERESTING[f]['abs_diff'] and abs(ratio) > _INTERESTING[f]['pct_diff']:
         self.final[f] = delta
     return self.final.keys()
@@ -209,16 +212,19 @@ for bm in comparables:
     js_old_opt = json.loads(f.read())
 
   for row in bm_json.expand_json(js_new_ctr, js_new_opt):
+    print row
     name = row['cpp_name']
     if name.endswith('_mean') or name.endswith('_stddev'): continue
     benchmarks[name].add_sample(row, True)
   for row in bm_json.expand_json(js_old_ctr, js_old_opt):
+    print row
     name = row['cpp_name']
     if name.endswith('_mean') or name.endswith('_stddev'): continue
     benchmarks[name].add_sample(row, False)
 
 really_interesting = set()
 for name, bm in benchmarks.items():
+  print name
   really_interesting.update(bm.process())
 fields = [f for f in args.track if f in args.track]