diff --git a/lib/solid_queue/configuration.rb b/lib/solid_queue/configuration.rb
index 713db5c01..61a715d89 100644
--- a/lib/solid_queue/configuration.rb
+++ b/lib/solid_queue/configuration.rb
@@ -40,6 +40,11 @@ def scheduler
       end
     end
 
+    def max_number_of_threads
+      # At most pool_size thread in each worker + 1 thread for the worker + 1 thread for the heartbeat task
+      queues.values.map { |queue| queue[:pool_size] }.max + 2
+    end
+
     private
       attr_reader :raw_config, :mode
 
diff --git a/lib/solid_queue/engine.rb b/lib/solid_queue/engine.rb
index b207409b5..eebef7567 100644
--- a/lib/solid_queue/engine.rb
+++ b/lib/solid_queue/engine.rb
@@ -19,7 +19,7 @@ class Engine < ::Rails::Engine
 
     initializer "solid_queue.app_executor", before: :run_prepare_callbacks do |app|
       config.solid_queue.app_executor    ||= app.executor
-      config.solid_queue.on_thread_error ||= -> (exception) { Rails.error.report(exception) }
+      config.solid_queue.on_thread_error ||= -> (exception) { Rails.error.report(exception, handled: false) }
 
       SolidQueue.app_executor = config.solid_queue.app_executor
       SolidQueue.on_thread_error = config.solid_queue.on_thread_error
diff --git a/test/unit/configuration_test.rb b/test/unit/configuration_test.rb
index fe3c9f208..ecfe307f2 100644
--- a/test/unit/configuration_test.rb
+++ b/test/unit/configuration_test.rb
@@ -15,4 +15,9 @@ class ConfigurationTest < ActiveSupport::TestCase
     assert_equal SolidQueue::Configuration::SCHEDULER_DEFAULTS[:polling_interval], configuration.scheduler.polling_interval
     assert configuration.workers.detect { |w| w.queue == "background" }.pool_size > 0
   end
+
+  test "max number of threads" do
+    configuration = SolidQueue::Configuration.new(mode: :all)
+    assert 7, configuration.max_number_of_threads
+  end
 end