feat: add support for CRITERION_HOME

.github/workflows/schedule-rust-bench.yml

@@ -60,8 +60,11 @@ jobs:
           run: |
             echo -e "\e[34mRunning rust benchmarks on dedicated machine fr1-spm15!\e[0m"
 
+            CRITERION_HOME=$(mktemp -d)
+            trap "rm -rf $CRITERION_HOME" INT TERM EXIT
+
             while IFS= read -r tgt; do
-                bazel run "$tgt"
+                bazel run "$tgt" -- --criterion-home "$CRITERION_HOME"
             done < <(bazel query "attr(tags, 'rust_bench', ${{ matrix.target }})")
 
             while IFS= read -r bench_dir; do
@@ -82,6 +85,6 @@ jobs:
                     >report.json
                 curl --fail --retry 2 -sS -o /dev/null -X POST -H 'Content-Type: application/json' --data @report.json \
                     "https://elasticsearch.testnet.dfinity.network/ci-performance-test/_doc"
-            done < <(find -L ./bazel-out -type d -path '*/new')
+            done < <(find -L "$CRITERION_HOME" -type d -path '*/new')
 
             echo -e "\e[34mRust benchmarks on dedicated machine fr1-spm15 finished.\e[0m"

bazel/generic_rust_bench.sh

@@ -2,6 +2,30 @@
 
 set -euo pipefail
 
+# criterion supports specifying a "home" where it places its benchmark result tree.
+# at the time of writing, our bazel version (.bazelversion) is outdated and sh_binary
+# does not support `env_inherit` so add (or rather intercept) a new CLI argument
+# `--criterion-home` which we convert into `CRITERION_HOME`, which is read by
+# criterion.rs.
+#
+# https://github.com/criterion-rs/criterion.rs/blob/950c3b727a09d10067ea686e2ac6f1f23569168f/src/lib.rs#L142-L142
+
+# store passthru args
+args=()
+while [[ $# -gt 0 ]]; do
+    case $1 in
+        --criterion-home)
+            shift
+            export CRITERION_HOME="$1"
+            ;;
+        *)
+            # passthru
+            args+=("$1")
+            shift
+            ;;
+    esac
+done
+
 # When Cargo runs benchmarks, it passes the --bench or --test command-line arguments to
 # the benchmark executables. Criterion.rs looks for these arguments and tries to either
 # run benchmarks or run in test mode. In particular, when you run cargo test --benches
@@ -11,7 +35,7 @@ set -euo pipefail
 # present, or when --bench and --test are both present.
 #
 # https://bheisler.github.io/criterion.rs/book/faq.html#when-i-run-benchmark-executables-directly-without-using-cargo-they-just-print-success-why
-CMD="${BAZEL_DEFS_BENCH_PREFIX}${BAZEL_DEFS_BENCH_BIN} --bench $@"
+CMD="${BAZEL_DEFS_BENCH_PREFIX}${BAZEL_DEFS_BENCH_BIN} --bench ${args[@]}"
 
 echo "running ${CMD}"
 ${CMD}