"However, since finding the right point through this method is both error-prone and time-consuming (diskplorer can take ages to collect all points). Scylla (and Seastar) now ships with scylla_io_setup (a wrapper around Seastar’s iotune) tool, that helps users find out what the recommended threshold is and configure the I/O scheduler properly."
It's a sidenote in the article, but a fantastic idea. I wish every major infrastructure component came with something like this, because the sad state today is that given a piece of tech, everyone has to tune each installation themselves, and there's a bazillion blog posts about each, and all of them containing conflicting information. And everytime you move to a new setup somewhere you have to remember all of that crap. Again.
There are other things that the I/O setup script will do as well, like making sure your filesystem can handle async I/O properly and is fully patched, etc. It is indeed designed to be run everytime anything major changes in your deployment (like if you deploy to other machines, add more disks, etc)
It's a sidenote in the article, but a fantastic idea. I wish every major infrastructure component came with something like this, because the sad state today is that given a piece of tech, everyone has to tune each installation themselves, and there's a bazillion blog posts about each, and all of them containing conflicting information. And everytime you move to a new setup somewhere you have to remember all of that crap. Again.