https://learninghub.kx.com/forums/topic/keeping-data-querable-while-processes-are-taking-down
If you had to take a process down for a short period of time (around 10 seconds) for a refresh. How can you ensure the data is still querable for clients during this process?
It is a good idea to have multiple processes with a load balancer in front. That way if one or more processes dies the others can still serve incoming requests.
If you have multiple processes and you need to restart them, you could do it one by one such that there is always at least one process available.