From 5998318f3af80c2ab46dd2efeafeb64456a99b70 Mon Sep 17 00:00:00 2001
From: Bernhard Manfred Gruber <bernhardmgruber@gmail.com>
Date: Thu, 6 Feb 2025 12:45:50 +0100
Subject: [PATCH] Clarify scan benchmarks

---
 cub/benchmarks/bench/scan/exclusive/{max.cu => custom.cu} | 6 ++++++
 cub/benchmarks/bench/scan/exclusive/sum.cu                | 2 ++
 2 files changed, 8 insertions(+)
 rename cub/benchmarks/bench/scan/exclusive/{max.cu => custom.cu} (87%)

diff --git a/cub/benchmarks/bench/scan/exclusive/max.cu b/cub/benchmarks/bench/scan/exclusive/custom.cu
similarity index 87%
rename from cub/benchmarks/bench/scan/exclusive/max.cu
rename to cub/benchmarks/bench/scan/exclusive/custom.cu
index 0bb946b49e8..592352467fd 100644
--- a/cub/benchmarks/bench/scan/exclusive/max.cu
+++ b/cub/benchmarks/bench/scan/exclusive/custom.cu
@@ -25,6 +25,12 @@
  *
  ******************************************************************************/
 
+// This benchmark uses a custom operation, max_t, which is not known to CUB, so no operator specific optimizations and
+// tunings are performed.
+
+// Because CUB cannot detect this operator, we cannot add any tunings based on the results of this benchmark. Its main
+// use is to detect regressions.
+
 // %RANGE% TUNE_ITEMS ipt 7:24:1
 // %RANGE% TUNE_THREADS tpb 128:1024:32
 // %RANGE% TUNE_MAGIC_NS ns 0:2048:4
diff --git a/cub/benchmarks/bench/scan/exclusive/sum.cu b/cub/benchmarks/bench/scan/exclusive/sum.cu
index 33e325c941f..678815165ac 100644
--- a/cub/benchmarks/bench/scan/exclusive/sum.cu
+++ b/cub/benchmarks/bench/scan/exclusive/sum.cu
@@ -25,6 +25,8 @@
  *
  ******************************************************************************/
 
+// Tuning parameters found for signed integer types apply equally for unsigned integer types
+
 #include <nvbench_helper.cuh>
 
 // %RANGE% TUNE_ITEMS ipt 7:24:1