diff --git a/.travis.yml b/.travis.yml
index 86dbcb2c09..618bd5f5e6 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -52,6 +52,7 @@ matrix:
     - rvm: ruby-head
       env: jit=yes
     - rvm: truffleruby
+    - rvm: 2.7.0-rc1
 
   allow_failures:
     - rvm: jruby-9.2.9.0
diff --git a/lib/puma/cluster.rb b/lib/puma/cluster.rb
index f68ad151ba..97ee976ba9 100644
--- a/lib/puma/cluster.rb
+++ b/lib/puma/cluster.rb
@@ -486,6 +486,7 @@ def run
       @master_read, @worker_write = read, @wakeup
 
       @launcher.config.run_hooks :before_fork, nil
+      GC.compact if GC.respond_to?(:compact)
 
       spawn_workers