diff --git a/util/threading.h b/util/threading.h
index 1b3ad41..14676b4 100644
--- a/util/threading.h
+++ b/util/threading.h
@@ -226,6 +226,8 @@ class NestedPools {
               BoundedSlice cluster_slice = BoundedSlice(),
               BoundedSlice lp_slice = BoundedSlice());
 
+  bool AllPinned() const { return all_pinned_; }
+
   // Subject to `use_spinning`, enables spin waits with the goal of reducing the
   // latency of barrier synchronization. We only spin during Generate to avoid
   // wasting energy during long waits. If `use_spinning` is kDefault, we first
diff --git a/util/threading_test.cc b/util/threading_test.cc
index 8e39616..4ca69ff 100644
--- a/util/threading_test.cc
+++ b/util/threading_test.cc
@@ -276,16 +276,27 @@ TEST(ThreadingTest, BenchJoin) {
   constexpr size_t kInputs = 1;
   static hwy::FuncInput inputs[kInputs];
 
-  const auto measure = [&](hwy::ThreadPool& pool, const char* caption) {
+  const auto measure = [&](hwy::ThreadPool& pool, bool spin,
+                           const char* caption) {
     inputs[0] =
         static_cast<hwy::FuncInput>(hwy::Unpredictable1() * pool.NumWorkers());
     hwy::Result results[kInputs];
     hwy::Params params;
     params.verbose = false;
     params.max_evals = kMaxEvals;
+
+    // Only spin for the duration of the benchmark to avoid wasting energy and
+    // interfering with the other pools.
+    if (spin) {
+      pool.SetWaitMode(hwy::PoolWaitMode::kSpin);
+    }
     const size_t num_results =
         Measure(&ForkJoin, reinterpret_cast<const uint8_t*>(&pool), inputs,
                 kInputs, results, params);
+    if (spin) {
+      pool.SetWaitMode(hwy::PoolWaitMode::kBlock);
+    }
+
     for (size_t i = 0; i < num_results; ++i) {
       printf("%-20s: %5d: %6.2f us; MAD=%4.2f%%\n", caption,
              static_cast<int>(results[i].input),
@@ -303,20 +314,19 @@ TEST(ThreadingTest, BenchJoin) {
   };
 
   NestedPools pools(0);
-  measure(pools.AllPackages(), "block packages");
+  measure(pools.AllPackages(), false, "block packages");
   if (pools.AllClusters(0).NumWorkers() > 1) {
-    measure(pools.AllClusters(0), "block clusters");
+    measure(pools.AllClusters(0), false, "block clusters");
   }
-  measure(pools.Cluster(0, 0), "block in_cluster");
+  measure(pools.Cluster(0, 0), false, "block in_cluster");
 
-  Tristate use_spinning = Tristate::kDefault;
-  pools.MaybeStartSpinning(use_spinning);
-  if (use_spinning == Tristate::kTrue) {
-    measure(pools.AllPackages(), "spin packages");
+  if (pools.AllPinned()) {
+    const bool kSpin = true;
+    measure(pools.AllPackages(), kSpin, "spin packages");
     if (pools.AllClusters(0).NumWorkers() > 1) {
-      measure(pools.AllClusters(0), "spin clusters");
+      measure(pools.AllClusters(0), kSpin, "spin clusters");
     }
-    measure(pools.Cluster(0, 0), "spin in_cluster");
+    measure(pools.Cluster(0, 0), kSpin, "spin in_cluster");
   }
 }