Set minimum heap size for native Turbine to 512 MB

src/java_tools/buildjar/java/com/google/devtools/build/java/turbine/BUILD

@@ -39,6 +39,13 @@ native_image(
         "--no-fallback",
         # More verbose errors in case of compilation failures.
         "-H:+ReportExceptionStackTraces",
+        # A benchmark on Bazel itself shows a ~15% improvement in combined compile and header
+        # compile action time on an incremental build triggered by a signature change to Label with
+        # this option. 256m provides a noticeably smaller improvement, higher values do not provide
+        # further improvement and would go over the local resource estimate in
+        # com.google.devtools.build.lib.rules.java.JavaCompileAction.LOCAL_RESOURCES.
+        # See :turbine_benchmark for the benchmark script used.
+        "-R:MinHeapSize=512m",
     ] + select({
         "@platforms//os:linux": [
             # Statically link zlib but not glibc.
@@ -59,6 +66,15 @@ native_image(
     deps = [":turbine_deps"],
 )
 
+# Run with -c opt.
+sh_binary(
+    name = "turbine_benchmark",
+    srcs = ["turbine_benchmark.sh"],
+    args = ["$(rlocationpath turbine_direct_graal)"],
+    data = [":turbine_direct_graal"],
+    deps = ["@bazel_tools//tools/bash/runfiles"],
+)
+
 filegroup(
     name = "srcs",
     srcs = glob(

src/java_tools/buildjar/java/com/google/devtools/build/java/turbine/turbine_benchmark.sh

@@ -0,0 +1,119 @@
+#!/usr/bin/env bash
+
+# Copyright 2023 The Bazel Authors. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Benchmarks prebuilt Turbine shipped in java_tools and Turbine built from HEAD on the following
+# scenario:
+# 1. Build the Bazel server jar in a full non-incremental build (disk cache +
+#    --experimental_java_classpath=bazel).
+# 2. Add a public method to Label.java.
+# 3. Benchmark the incremental build, which consists of both Java compile and header compile
+#    actions.
+#
+# The profiles for the last run of each benchmark are kept in the root directory.
+#
+# Requires the following tools to be installed on the host:
+# - hyperfine (https://github.com/sharkdp/hyperfine)
+# - buildozer (https://github.com/bazelbuild/buildtools/tree/master/buildozer)
+
+# --- begin runfiles.bash initialization v3 ---
+# Copy-pasted from the Bazel Bash runfiles library v3.
+set -uo pipefail; set +e; f=bazel_tools/tools/bash/runfiles/runfiles.bash
+source "${RUNFILES_DIR:-/dev/null}/$f" 2>/dev/null || \
+  source "$(grep -sm1 "^$f " "${RUNFILES_MANIFEST_FILE:-/dev/null}" | cut -f2- -d' ')" 2>/dev/null || \
+  source "$0.runfiles/$f" 2>/dev/null || \
+  source "$(grep -sm1 "^$f " "$0.runfiles_manifest" | cut -f2- -d' ')" 2>/dev/null || \
+  source "$(grep -sm1 "^$f " "$0.exe.runfiles_manifest" | cut -f2- -d' ')" 2>/dev/null || \
+  { echo>&2 "ERROR: cannot find $f"; exit 1; }; f=; set -e
+# --- end runfiles.bash initialization v3 ---
+
+# Disable MSYS path conversion, which can otherwise mess up Bazel labels.
+export MSYS2_ARG_CONV_EXCL='*'
+export MSYS_NO_PATHCONV=1
+
+RUNS=5
+TMPDIR="${TMPDIR:-/tmp}"
+
+export DISK_CACHE="$TMPDIR/turbine_benchmark_disk_cache"
+export BAZEL_TARGET='//src/main/java/com/google/devtools/build/lib/bazel:BazelServer'
+export FILE_TO_MODIFY='src/main/java/com/google/devtools/build/lib/cmdline/Label.java'
+
+function reset_file() {
+  git checkout -- "$FILE_TO_MODIFY"
+}
+export -f reset_file
+
+function reset_and_modify_file() {
+  reset_file
+  # Add a public method with a unique name to the file to ensure that the incremental build is
+  # not using any cached results.
+  sed -i"" -e "s/^}/  public void foo$(uuid | tr '-' '_')() {}\n}/g" "$FILE_TO_MODIFY"
+}
+export -f reset_and_modify_file
+
+function build_target() {
+  # Keep the last profile around after a benchmark
+  bazel build --experimental_java_classpath=bazel \
+    --disk_cache="$DISK_CACHE" \
+    --extra_toolchains=//_turbine_benchmark:turbine_benchmark_toolchain_definition \
+    --profile="${PROFILE_PATH:-}" \
+    $BAZEL_TARGET
+}
+export -f build_target
+
+mkdir -p "$DISK_CACHE"
+mkdir -p "$BUILD_WORKSPACE_DIRECTORY/_turbine_benchmark"
+TURBINE_PATH="$(rlocation "$1")"
+if [[ ! "$TURBINE_PATH" =~ "-opt/" ]]; then
+  echo "ERROR: benchmark must be executed with -c opt"
+  exit 1
+fi
+cp "$TURBINE_PATH" "$BUILD_WORKSPACE_DIRECTORY/_turbine_benchmark/turbine"
+# Change directory only after accessing runfiles as rlocation may returns paths relative to the
+# initial working directory.
+cd "$BUILD_WORKSPACE_DIRECTORY"
+
+function cleanup() {
+  rm -rf _turbine_benchmark
+  reset_file
+  # Do not delete the disk cache to avoid rebuilding Bazel every time the script is executed.
+}
+trap cleanup EXIT INT TERM
+
+function run_benchmark() {
+  # Cache a full non-incremental build.
+  build_target
+  # Change a file and benchmark the incremental build.
+  hyperfine --shell=bash --warmup 1 --runs $RUNS --prepare reset_and_modify_file build_target
+}
+
+echo "===== Benchmarking prebuilt Turbine ====="
+cat << 'EOF' > _turbine_benchmark/BUILD
+load("@rules_java//toolchains:default_java_toolchain.bzl", "default_java_toolchain")
+default_java_toolchain(
+    name = "turbine_benchmark_toolchain",
+    source_version = "11",
+    target_version = "11",
+    # Work around for https://github.com/bazelbuild/bazel/issues/19837.
+    bootclasspath = ["@rules_java//toolchains:platformclasspath"],
+)
+EOF
+export PROFILE_PATH=with_prebuilt_turbine.profile.gz
+run_benchmark
+
+echo "===== Benchmarking Turbine built from HEAD ====="
+buildozer 'add header_compiler_direct turbine' //_turbine_benchmark:turbine_benchmark_toolchain
+export PROFILE_PATH=with_head_turbine.profile.gz
+run_benchmark