ROS Resources: Documentation | Support | Discussion Forum | Index | Service Status | ros @ Robotics Stack Exchange
Ask Your Question
10

rospy.Publisher: what's a good choice for queue_size?

asked 2014-08-15 16:15:34 -0600

Rick Armstrong gravatar image

Hello,

We just switched over to using Indigo, and noticed the warnings about using rospy.Publisher without specifying a queue_size. I've read this and I can see that it's a fabulous idea to specify this value. What's a good value to use, and how do I know if I've picked a reasonable number?

Thanks,

Rick

edit retag flag offensive close merge delete

1 Answer

Sort by » oldest newest most voted
11

answered 2014-08-16 23:00:48 -0600

tfoote gravatar image

The queue size is a balance between latency and completeness. If your usage only wants the latest data a small queue size is appropriate. If your application would rather have more complete information a larger queue size is preferred.

Note it will only be an issue if your topic backs up. Another consideration is if the publisher will be pushing multiple messages close together make sure the queue is big enough to hold the whole batch if you don't want losses.

edit flag offensive delete link more

Comments

Thanks Tully,

Rick

Rick Armstrong gravatar image Rick Armstrong  ( 2014-08-17 15:20:13 -0600 )edit

Are there any performance or efficiency concerns connected to the queue size? I.e. does a smaller queue size save memory or is there no gain of a small queue size over a large queue size?

Paddre gravatar image Paddre  ( 2017-07-22 05:17:56 -0600 )edit

Question Tools

1 follower

Stats

Asked: 2014-08-15 16:15:34 -0600

Seen: 6,528 times

Last updated: Aug 16 '14