diff --git a/bench/scripts/compiler.sh b/bench/scripts/compiler.sh
index 246ef6bc334d..9612c2459afb 100755
--- a/bench/scripts/compiler.sh
+++ b/bench/scripts/compiler.sh
@@ -1,2 +1,2 @@
 #!/usr/bin/env bash
-find compiler/src/ -type f \( -name "*.scala" -or -name "*.java" \) -exec echo "dotty-bench/jmh:run" {} + | sbt
+find compiler/src/ -type f \( -name "*.scala" -or -name "*.java" \) -exec echo "dotty-bench/jmh:run 5 10" {} + | sbt
diff --git a/bench/scripts/library.sh b/bench/scripts/library.sh
index 54724bbbd8f2..ef02ea898398 100755
--- a/bench/scripts/library.sh
+++ b/bench/scripts/library.sh
@@ -1,2 +1,2 @@
 #!/usr/bin/env bash
-find library/src/ -type f \( -name "*.scala" -or -name "*.java" \) -exec echo "dotty-bench/jmh:run" {} + | sbt
+find library/src/ -type f \( -name "*.scala" -or -name "*.java" \) -exec echo "dotty-bench/jmh:run 40 30" {} + | sbt
diff --git a/bench/src/main/scala/Benchmarks.scala b/bench/src/main/scala/Benchmarks.scala
index 03e0c2302479..608dba8006a1 100644
--- a/bench/src/main/scala/Benchmarks.scala
+++ b/bench/src/main/scala/Benchmarks.scala
@@ -22,8 +22,12 @@ object Bench {
       println("Missing <args>")
       return
     }
+    val (intArgs, args1) = args.span(x => try { x.toInt; true } catch { case _: Throwable => false } )
 
-    val args2 = args.map { arg =>
+    val warmup = if (intArgs.length > 0) intArgs(0).toInt else 30
+    val iteration warmup = if (intArgs.length > 1) intArgs(1).toInt else 20
+
+    val args2 = args1.map { arg =>
       if ((arg.endsWith(".scala") || arg.endsWith(".java")) && arg.head != '/') "../" + arg
       else arg
     }
@@ -36,8 +40,8 @@ object Bench {
                .mode(Mode.AverageTime)
                .timeUnit(TimeUnit.MILLISECONDS)
                .forks(1)
-               .warmupIterations(30)
-               .measurementIterations(20)
+               .warmupIterations(warmup)
+               .measurementIterations(iterations)
                .build
 
     val runner = new Runner(opts) // full access to all JMH features, you can also provide a custom output Format here