diff --git a/compiler/test/dotty/tools/dotc/CompilationTests.scala b/compiler/test/dotty/tools/dotc/CompilationTests.scala
index cf9b200d4631..a5914bf4d23c 100644
--- a/compiler/test/dotty/tools/dotc/CompilationTests.scala
+++ b/compiler/test/dotty/tools/dotc/CompilationTests.scala
@@ -15,7 +15,7 @@ class CompilationTests extends ParallelTesting {
 
   // Test suite configuration --------------------------------------------------
 
-  def maxDuration = 180.seconds
+  def maxDuration = 30.seconds
   def numberOfSlaves = 5
   def safeMode = Properties.testsSafeMode
   def isInteractive = SummaryReport.isInteractive
diff --git a/tests/run/t2417.check b/tests/disabled/long-running/t2417.check
similarity index 100%
rename from tests/run/t2417.check
rename to tests/disabled/long-running/t2417.check
diff --git a/tests/run/t2417.scala b/tests/disabled/long-running/t2417.scala
similarity index 100%
rename from tests/run/t2417.scala
rename to tests/disabled/long-running/t2417.scala
diff --git a/tests/run/t3242.scala b/tests/disabled/long-running/t3242.scala
similarity index 100%
rename from tests/run/t3242.scala
rename to tests/disabled/long-running/t3242.scala
diff --git a/tests/run/t4459.scala b/tests/disabled/long-running/t4459.scala
similarity index 100%
rename from tests/run/t4459.scala
rename to tests/disabled/long-running/t4459.scala
diff --git a/tests/run/t6253a.scala b/tests/disabled/long-running/t6253a.scala
similarity index 100%
rename from tests/run/t6253a.scala
rename to tests/disabled/long-running/t6253a.scala
diff --git a/tests/run/t6253b.scala b/tests/disabled/long-running/t6253b.scala
similarity index 100%
rename from tests/run/t6253b.scala
rename to tests/disabled/long-running/t6253b.scala
diff --git a/tests/run/t6253c.scala b/tests/disabled/long-running/t6253c.scala
similarity index 100%
rename from tests/run/t6253c.scala
rename to tests/disabled/long-running/t6253c.scala
diff --git a/tests/run/vector1.scala b/tests/disabled/long-running/vector1.scala
similarity index 100%
rename from tests/run/vector1.scala
rename to tests/disabled/long-running/vector1.scala
diff --git a/tests/run/t3989.scala b/tests/run/t3989.scala
deleted file mode 100644
index 896283f19c0a..000000000000
--- a/tests/run/t3989.scala
+++ /dev/null
@@ -1,17 +0,0 @@
-
-
-
-
-
-class Foo{ override def equals(o: Any) = false; override def hashCode = 1}
-
-// should not result in a stack overflow
-object Test {
-  def main(args: Array[String]): Unit = {
-    import collection.immutable.HashMap
-    var m = Map[Foo, Int]()
-    for (i <- 1 to 30000) m += (new Foo) -> i
-    assert(m.size == 30000)
-    m.toString
-  }
-}
diff --git a/tests/run/t6853.scala b/tests/run/t6853.scala
deleted file mode 100644
index 352375c99c49..000000000000
--- a/tests/run/t6853.scala
+++ /dev/null
@@ -1,18 +0,0 @@
-// Test cases: the only place we can cut and paste without crying
-// ourself to sleep.
-object Test {
-
-  def main(args: Array[String]): Unit = {
-    // First testing the basic operations
-    val m = collection.mutable.ListMap[String, Int]()
-    var i = 0
-    while(i < 2) { m += ("foo" + i) -> i; i = i+1}
-    assert(m == Map("foo1"->1,"foo0"->0))
-    m-= "foo0"
-    assert(m == Map("foo1"->1))
-    // Now checking if it scales as described in SI-6853
-    i = 0
-    while(i < 80000) { m += ("foo" + i) -> i; i = i+1}
-    assert(m.size == 80000)
-  }
-}