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Larger timeout value animation question

I’m not sure if I’m being exceptionally dense right now, but I’m not catching the intuition in the second animation in this lesson. The longer timeout value gives Node B more time to reply, which makes sense. So it replies, and Node A receives the reply. But then it sends out the question again… And a red X appears.

I’m guessing the red X means Node B dies after sending its message, but is that not a possibility with lower timeout values too? A node can crash immediately after sending a message when short timeout values are used…
A longer timeout value also does not necessarily mean that fewer total requests are sent or that they are sent less frequently. Just that each one can possibly have more latency.

I’m clearly missing something. I’d appreciate a point in the right direction. Thanks!


Course: Distributed Systems for Practitioners - Learn Interactively
Lesson: Failure in the World of Distributed Systems - Distributed Systems for Practitioners

Hi @David_Andrea, Thank you for contacting the Educative team with your query!
Actually, the lessons focus on the failures of the distributed system, both the animations show the problems and failed results due to the value of the timeout.
Animation One says that if the timeout value is less or small then it considers the final results before the response have been sent back from the other end .
On the contrary, animation two shows the failures occur when the timeout value is greater than it may be slower in identifying crashed nodes, the red X means the crashed nodes in some cases wasting time while waiting for them.

Hope this answer your query, Please feel free to reply here if there is still some confusion.

Hope you have an amazing learning experience on Educative!

that should not be the case. time out values are not like sliding window periods, where the next request will only go after the current timeout values have elapsed.