# Bringing up a node through roslaunch from a remote machine and through local roslaunch gives different publishing rates

I have two machines A and B. I want to start node N on machine B. Node N publishes topic T.

case 1: Use launch file in machine A to remotely launch node N on machine B. case 2: Ssh in to machine B and launch node N on machine B locally.

I assumed both these cases were identical with regards to the ROS system. However I am seeing significant differences and I would like some help understanding them.

When I do a rostopic hz on topic T, I see different results between case 1 and case 2

case 1: 6 hz on B, 5 hz on A
case 2: 14 hz on B, 13 hz on A


I understand that small variations between rostopic hz numbers between machines A and B could be due to my network loads. I don't understand the big drop in hz values between case 1 and case 2.

Any help would be great. Thanks.

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