adding rate loops where applicable

nav2_costmap_2d/src/costmap_2d_ros.cpp

@@ -102,6 +102,7 @@ Costmap2DROS::Costmap2DROS(const std::string & name, tf2_ros::Buffer & tf)
 
   // we need to make sure that the transform between the robot base frame
   // and the global frame is available
+  auto sleep_dir = std::chrono::milliseconds(100);
   while (rclcpp::ok() &&
     !tf_.canTransform(global_frame_, robot_base_frame_, tf2::TimePointZero,
     tf2::durationFromSec(0.1), &tf_error))
@@ -116,6 +117,7 @@ Costmap2DROS::Costmap2DROS(const std::string & name, tf2_ros::Buffer & tf)
     // The error string will accumulate and errors will typically be the same, so the last
     // will do for the warning above. Reset the string here to avoid accumulation.
     tf_error.clear();
+    rclcpp::sleep_for(sleep_dir);
   }
 
   // check if we want a rolling window version of the costmap
@@ -382,7 +384,7 @@ void Costmap2DROS::start()
   stop_updates_ = false;
 
   // block until the costmap is re-initialized.. meaning one update cycle has run
-  rclcpp::Rate r(100.0);
+  rclcpp::Rate r(20.0);
   while (rclcpp::ok() && !initialized_) {
     r.sleep();
   }

nav2_map_server/src/map_saver.cpp

@@ -99,9 +99,10 @@ int main(int argc, char ** argv)
   auto map_gen = std::make_shared<nav2_map_server::MapGenerator>(mapname, threshold_occupied,
       threshold_free);
 
+  auto sleep_dir = std::chrono::milliseconds(100);
   while (!map_gen->saved_map_ && rclcpp::ok()) {
     rclcpp::spin_some(map_gen);
-    rclcpp::sleep_for(100ms);
+    rclcpp::sleep_for(sleep_dir);
   }
 
   rclcpp::shutdown();

nav2_util/include/nav2_util/service_client.hpp

@@ -58,10 +58,12 @@ class ServiceClient
 
   void wait_for_service(const std::chrono::seconds timeout = std::chrono::seconds::max())
   {
+    auto sleep_dir = std::chrono::milliseconds(10);
     while (!client_->wait_for_service(timeout)) {
       if (!rclcpp::ok()) {
         throw std::runtime_error("waitForServer: interrupted while waiting for service to appear");
       }
+      rclcpp::sleep_for(sleep_dir);
     }
   }