Hello all,

I am running a navigation stack having /tf frames as:
/map -> /odom -> /base_link -> /base_laser_link
I get non stop warning messages after receiving map (default: Willow garage 
bag file for map) by the system such as:

[ WARN] 1277968643.538585000: Costmap2DROS transform timeout. Current time: 
1277968643.5385, global_pose stamp: 1277968641.9836, tolerance: 0.2000
[ WARN] 1277968643.729229000: Costmap2DROS transform timeout. Current time: 
1277968643.7292, global_pose stamp: 1277968641.9950, tolerance: 0.3000
[ WARN] 1277968643.754345000: Costmap2DROS transform timeout. Current time: 
1277968643.7543, global_pose stamp: 1277968641.9836, tolerance: 0.2000
[ WARN] 1277968643.929851000: Costmap2DROS transform timeout. Current time: 
1277968643.9298, global_pose stamp: 1277968641.9950, tolerance: 0.3000
[ WARN] 1277968643.945697000: Costmap2DROS transform timeout. Current time: 
1277968643.9456, global_pose stamp: 1277968641.9836, tolerance: 0.2000

With reference to the older post i tried to track down the avg. latency 
time through tf debug view_frames; the pdf result was:
       
/Map -> /odom
  Broadcaster: /amcl
       Average rate: 5.307 Hz
Most recent transform: 0.758 sec old
      Buffer length: 3.769 sec

/odom -> /base_link
         Broadcaster: /odom
       Average rate: 1.250 Hz
Most recent transform: 0.206 sec old
      Buffer length: 4.001 sec

and through tf_monitor
Node: /amcl 9.10341 Hz, Average Delay: 0.632831 Max Delay: 0.993998
Node: /broadcaster 99.9929 Hz, Average Delay: 0.000343028 Max Delay: 
0.00455
Node: /odom 2.00006 Hz, Average Delay: 0.000208 Max Delay: 0.000216

My .yaml file configurations are:
global_costmap:
  global_frame: /map
  robot_base_frame: base_link
# Update at frequency
  update_frequency: 5.0
  static_map: true
# Tolerable delay 
  transform_tolerance: 0.2 

local_costmap:
  global_frame: odom
  robot_base_frame: base_link
  update_frequency: 5.0
  publish_frequency: 2.0
  static_map: false
  rolling_window: true
  width: 6.0
  height: 6.0
  resolution: 0.05

I tried to change update, publish frequencies and also the tolerances with 
different values but i could not make out required frequency.
I don't want to up tolerance parameter since it may allow older transform.

Please let me know if any other parameter present which may help me to 
reduce delay time.

-Prasad Dixit