From 7de44dc93cbfbebfb847ff284b678254a1647883 Mon Sep 17 00:00:00 2001
From: filzrev <103790468+filzrev@users.noreply.github.com>
Date: Sun, 27 Apr 2025 18:34:10 +0900
Subject: [PATCH] feat: add option to disable parallel build

---
 src/BenchmarkDotNet/Configs/ConfigOptions.cs  |  6 +++-
 .../Running/BenchmarkRunnerClean.cs           | 31 ++++++++++++++++++-
 2 files changed, 35 insertions(+), 2 deletions(-)

diff --git a/src/BenchmarkDotNet/Configs/ConfigOptions.cs b/src/BenchmarkDotNet/Configs/ConfigOptions.cs
index c1ad75d642..06bc7768c7 100644
--- a/src/BenchmarkDotNet/Configs/ConfigOptions.cs
+++ b/src/BenchmarkDotNet/Configs/ConfigOptions.cs
@@ -48,7 +48,11 @@ public enum ConfigOptions
         /// <summary>
         /// Continue the execution if the last run was stopped.
         /// </summary>
-        Resume = 1 << 9
+        Resume = 1 << 9,
+        /// <summary>
+        /// Determines whether parallel build of benchmark projects should be disabled.
+        /// </summary>
+        DisableParallelBuild = 1 << 10,
     }
 
     internal static class ConfigOptionsExtensions
diff --git a/src/BenchmarkDotNet/Running/BenchmarkRunnerClean.cs b/src/BenchmarkDotNet/Running/BenchmarkRunnerClean.cs
index 4f520da38d..12773880fc 100644
--- a/src/BenchmarkDotNet/Running/BenchmarkRunnerClean.cs
+++ b/src/BenchmarkDotNet/Running/BenchmarkRunnerClean.cs
@@ -88,7 +88,11 @@ internal static Summary[] Run(BenchmarkRunInfo[] benchmarkRunInfos)
 
                 var buildPartitions = BenchmarkPartitioner.CreateForBuild(supportedBenchmarks, resolver);
                 eventProcessor.OnStartBuildStage(buildPartitions);
-                var buildResults = BuildInParallel(compositeLogger, rootArtifactsFolderPath, buildPartitions, in globalChronometer, eventProcessor);
+
+                bool useParallelBuild = !supportedBenchmarks.Any(x => x.Config.Options.IsSet(ConfigOptions.DisableParallelBuild));
+                var buildResults = useParallelBuild
+                    ? BuildInParallel(compositeLogger, rootArtifactsFolderPath, buildPartitions, in globalChronometer, eventProcessor)
+                    : BuildSequential(compositeLogger, rootArtifactsFolderPath, buildPartitions, in globalChronometer, eventProcessor);
 
                 var allBuildsHaveFailed = buildResults.Values.All(buildResult => !buildResult.IsBuildSuccess);
 
@@ -413,6 +417,31 @@ static string GetFormattedDifference(ClockSpan before, ClockSpan after)
                 => (after.GetTimeSpan() - before.GetTimeSpan()).ToFormattedTotalTime(DefaultCultureInfo.Instance);
         }
 
+        private static Dictionary<BuildPartition, BuildResult> BuildSequential(ILogger logger, string rootArtifactsFolderPath, BuildPartition[] buildPartitions, in StartedClock globalChronometer, EventProcessor eventProcessor)
+        {
+            logger.WriteLineHeader($"// ***** Building {buildPartitions.Length} exe(s): Start   *****");
+
+            var buildLogger = buildPartitions.Length == 1 ? logger : NullLogger.Instance; // when we have just one partition we can print to std out
+
+            var beforeBuild = globalChronometer.GetElapsed();
+
+            var buildResults = new Dictionary<BuildPartition, BuildResult>();
+            foreach (var buildPartition in buildPartitions)
+            {
+                buildResults[buildPartition] = Build(buildPartition, rootArtifactsFolderPath, buildLogger);
+                eventProcessor.OnBuildComplete(buildPartition, buildResults[buildPartition]);
+            }
+
+            var afterBuild = globalChronometer.GetElapsed();
+
+            logger.WriteLineHeader($"// ***** Done, took {GetFormattedDifference(beforeBuild, afterBuild)}   *****");
+
+            return buildResults;
+
+            static string GetFormattedDifference(ClockSpan before, ClockSpan after)
+                => (after.GetTimeSpan() - before.GetTimeSpan()).ToFormattedTotalTime(DefaultCultureInfo.Instance);
+        }
+
         private static BuildResult Build(BuildPartition buildPartition, string rootArtifactsFolderPath, ILogger buildLogger)
         {
             var toolchain = buildPartition.RepresentativeBenchmarkCase.GetToolchain(); // it's guaranteed that all the benchmarks in single partition have same toolchain