Benchmarks: Automatically detect which cores to run contenders on

1 files changed, 13 insertions, 8 deletions

diff --git a/run_bench.sh b/run_bench.sh
index cf94719..6e4abb5 100755
--- a/run_bench.sh
+++ b/run_bench.sh
@@ -304,15 +304,20 @@ echo "Press enter to confirm environment, Ctrl-C to exit..."
 read
 
 # Start contending tasks
+# If we're on CPU 15, this would launch contenders on CPUs 0, 1, 4, 5, 8, and 9
 if [[ -v contend ]]; then
-    echo "Done. Starting 6 contending tasks..."
-    # Run two contending tasks on each other CCX
-    taskset -c 1 ../thrasher/thrasher &
-    taskset -c 2 ../thrasher/thrasher &
-    taskset -c 5 ../thrasher/thrasher &
-    taskset -c 6 ../thrasher/thrasher &
-    taskset -c 9 ../thrasher/thrasher &
-    taskset -c 10 ../thrasher/thrasher &
+    echo "Done. Starting contending tasks on other CCXes..."
+    num_phys_cores=$(grep -m 1 "cpu cores" /proc/cpuinfo | cut -d " " -f 3)
+    # For each set of 4 cores (CCX)
+    for (( i = 0; i < ${num_phys_cores} ; i += 4 )); do
+        # Don't run contending tasks on the CCX we're benchmarking
+        if (($core / 4 == $i / 4)); then
+            continue
+        fi
+        # Otherwise launch on the other two
+        taskset -c $i ../thrasher/thrasher &
+        taskset -c $(($i+1)) ../thrasher/thrasher &
+    done
 fi
 sleep 1 # Wait for contending tasks to start
 echo "Done. Beginning benchmarks..."