Despite a recent git fetch https://gitlab.haskell.org/ghc/ghc-performance-notes.git refs/notes/perf:refs/notes/ci/perf I'm getting lots of perf regressions in HEAD. For example =====> T9203(normal) 1 of 1 [0, 0, 0] ]0;T9203(normal) 1 of 1 [0, 0, 0]cd "T9203.run" && "/home/simonpj/code/HEAD-3/inplace/bin/ghc-stage2" -o T9203 T9203.hs -dcore-lint -dstg-lint -dcmm-lint -no-user-package-db -rtsopts -fno-warn-missed-specialisations -fshow-warning-groups -fdiagnostics-color=never -fno-diagnostics-show-caret -Werror=compat -dno-debug-output -O2< cd "T9203.run" && ./T9203 +RTS -V0 -tT9203.stats --machine-readable -RTS < runtime/bytes allocated increased from x86_64-linux-deb9 baseline @ HEAD~28: Expected T9203 (normal) runtime/bytes allocated: 56046952.0 +/-5% Lower bound T9203 (normal) runtime/bytes allocated: 53244604 Upper bound T9203 (normal) runtime/bytes allocated: 58849300 Actual T9203 (normal) runtime/bytes allocated: 108464536 Deviation T9203 (normal) runtime/bytes allocated: 93.5 % *** unexpected stat test failure for T9203(normal) Performance Metrics (test environment: local): T9203(normal) runtime/bytes allocated 108464536.000 (baseline @ HEAD~28) 56046952.000 [increased, 93.5%] What am I doing wrong? Simon