diff --git a/tests/bench/accumulate_profile.py b/tests/bench/accumulate_profile.py
index 50d9980346..a018f83d0f 100755
--- a/tests/bench/accumulate_profile.py
+++ b/tests/bench/accumulate_profile.py
@@ -4,10 +4,11 @@ import collections
 import re
 import sys
 
-data = sys.stdin.read()
 cats = collections.defaultdict(lambda: 0)
-for m in re.findall("^(.+?) ([\d.]+)(m?)s$", data, re.MULTILINE):
-    cats[m[0].strip()] += float(m[1]) * (1e-3 if m[2] else 1)
+for line in sys.stdin:
+    if m := re.match("(.+?) ([\d.]+)(m?)s", line):
+        cats[m[1].strip()] += float(m[2]) * (1e-3 if m[3] else 1)
+    sys.stderr.write(line)
 
 for cat in sorted(cats.keys()):
     cat2 = cat
diff --git a/tests/bench/speedcenter.exec.velcom.yaml b/tests/bench/speedcenter.exec.velcom.yaml
index 9b2cf948b4..764759e5ad 100644
--- a/tests/bench/speedcenter.exec.velcom.yaml
+++ b/tests/bench/speedcenter.exec.velcom.yaml
@@ -11,13 +11,13 @@
   run_config:
     <<: *time
     cmd: |
-      bash -c 'set -eo pipefail; make LEAN_OPTS="-Dprofiler=true -Dprofiler.threshold=9999" -C ${BUILD:-../../build/release}/stage2 --output-sync --always-make -j$(nproc) make_stdlib 2>&1 > log | ./accumulate_profile.py'
+      bash -c 'set -eo pipefail; touch ../../src/Init/Prelude.lean; make LEAN_OPTS="-Dprofiler=true -Dprofiler.threshold=9999" -C ${BUILD:-../../build/release}/stage2 --output-sync -j$(nproc) make_stdlib 2>&1 | ./accumulate_profile.py'
     max_runs: 2
     parse_output: true
   # initialize stage2 cmake + warmup
   build_config:
     cmd: |
-      bash -c 'make -C ${BUILD:-../../build/release} stage2 -j8'
+      bash -c 'make -C ${BUILD:-../../build/release} stage2 -j$(nproc)'
 - attributes:
     description: stdlib size
     tags: [deterministic, fast]