fix: Sporadic failure of GoblinRecursionTests.Vanilla (#6218)

The test in question would fail sporadically. It was fixed by disabling
multithreading for certain loops in the MSM builder. This introduces a
small regression which is probably not worth fixing (.16s in WASM).

For more info, see the PR description.

barretenberg/cpp/scripts/compare_branch_vs_baseline.sh

@@ -0,0 +1,61 @@
+#!/usr/bin/env bash
+
+# Install requirements (numpy + scipy) for comparison script if necessary.
+# Note: By default, installation will occur in $HOME/.local/bin.
+# pip3 install --user -r $BUILD_DIR/_deps/benchmark-src/requirements.txt
+
+
+# This script is used to compare a suite of benchmarks between baseline (default: master) and
+# the branch from which the script is run. Simply check out the branch of interest, ensure
+# it is up to date with local master, and run the script.
+
+# Specify the benchmark suite and the "baseline" branch against which to compare
+BENCHMARK=${1:-goblin_bench}
+FILTER=${2:-""}
+PRESET=${3:-clang16}
+BUILD_DIR=${4:-build}
+HARDWARE_CONCURRENCY=${HARDWARE_CONCURRENCY:-16}
+
+BASELINE_BRANCH="master"
+BENCH_TOOLS_DIR="$BUILD_DIR/_deps/benchmark-src/tools"
+
+echo -e "\nComparing $BENCHMARK between $BASELINE_BRANCH and current branch:"
+
+# Move above script dir.
+cd $(dirname $0)/..
+
+# Configure and build benchmark in feature branch
+echo -e "\nConfiguring and building $BENCHMARK in current feature branch...\n"
+cmake --preset $PRESET
+cmake --build --preset $PRESET --target $BENCHMARK
+
+# Run bench in current branch
+echo -e "\nRunning benchmark in feature branch.."
+./scripts/benchmark.sh $BENCHMARK\
+                        "./$BENCHMARK --benchmark_filter=$FILTER\
+                                      --benchmark_out=results_after.json\
+                                      --benchmark_out_format=json"\
+                        $PRESET
+                        $BUILD_DIR
+
+# Configure and build benchmark in $BASELINE branch
+echo -e "\nConfiguring and building $BENCHMARK in $BASELINE_BRANCH...\n"
+git checkout $BASELINE_BRANCH
+cmake --preset $PRESET
+cmake --build --preset $PRESET --target $BENCHMARK
+
+# Run bench in current branch
+echo -e "\nRunning benchmark in feature branch.."
+./scripts/benchmark.sh $BENCHMARK\
+                        "./$BENCHMARK --benchmark_filter=$FILTER\
+                                      --benchmark_out=results_before.json\
+                                      --benchmark_out_format=json"\
+                        $PRESET
+                        $BUILD_DIR
+
+# Call compare.py on the results (json) to get high level statistics.
+# See docs at https://github.com/google/benchmark/blob/main/docs/tools.md for more details.
+$BENCH_TOOLS_DIR/compare.py benchmarks $BUILD_DIR/results_before.json $BUILD_DIR/results_after.json
+
+# Return to branch from which the script was called
+git checkout -

barretenberg/cpp/scripts/compare_branch_vs_baseline_remote.sh

@@ -0,0 +1,65 @@
+#!/usr/bin/env bash
+
+# Install requirements (numpy + scipy) for comparison script if necessary.
+# Note: By default, installation will occur in $HOME/.local/bin.
+# pip3 install --user -r $BUILD_DIR/_deps/benchmark-src/requirements.txt
+
+
+# This script is used to compare a suite of benchmarks between baseline (default: master) and
+# the branch from which the script is run. Simply check out the branch of interest, ensure
+# it is up to date with local master, and run the script.
+
+# Specify the benchmark suite and the "baseline" branch against which to compare
+BENCHMARK=${1:-goblin_bench}
+FILTER=${2:-""}
+PRESET=${3:-clang16}
+BUILD_DIR=${4:-build}
+HARDWARE_CONCURRENCY=${HARDWARE_CONCURRENCY:-16}
+
+BASELINE_BRANCH="master"
+BENCH_TOOLS_DIR="$BUILD_DIR/_deps/benchmark-src/tools"
+
+echo -e "\nComparing $BENCHMARK between $BASELINE_BRANCH and current branch:"
+
+# Move above script dir.
+cd $(dirname $0)/..
+
+# Configure and build benchmark in feature branch
+echo -e "\nConfiguring and building $BENCHMARK in current feature branch...\n"
+cmake --preset $PRESET
+cmake --build --preset $PRESET --target $BENCHMARK
+
+# Run bench in current branch
+echo -e "\nRunning benchmark in feature branch.."
+./scripts/benchmark_remote.sh $BENCHMARK\
+                              "./$BENCHMARK --benchmark_filter=$FILTER\
+                                            --benchmark_out=results_after.json\
+                                            --benchmark_out_format=json"\
+                              $PRESET\
+                              $BUILD_DIR
+
+scp $BB_SSH_KEY $BB_SSH_INSTANCE:$BB_SSH_CPP_PATH/build/results_after.json $BUILD_DIR/
+
+# Configure and build benchmark in $BASELINE branch
+echo -e "\nConfiguring and building $BENCHMARK in $BASELINE_BRANCH...\n"
+git checkout $BASELINE_BRANCH
+cmake --preset $PRESET
+cmake --build --preset $PRESET --target $BENCHMARK
+
+# Run bench in current branch
+echo -e "\nRunning benchmark in feature branch.."
+./scripts/benchmark_remote.sh $BENCHMARK\
+                              "./$BENCHMARK --benchmark_filter=$FILTER\
+                                            --benchmark_out=results_before.json\
+                                            --benchmark_out_format=json"\
+                              $PRESET\
+                              $BUILD_DIR
+
+scp $BB_SSH_KEY $BB_SSH_INSTANCE:$BB_SSH_CPP_PATH/build/results_before.json $BUILD_DIR/
+
+# Call compare.py on the results (json) to get high level statistics.
+# See docs at https://github.com/google/benchmark/blob/main/docs/tools.md for more details.
+$BENCH_TOOLS_DIR/compare.py benchmarks $BUILD_DIR/results_before.json $BUILD_DIR/results_after.json
+
+# Return to branch from which the script was called
+git checkout -