Per discussion in Zulip thread, we should add a note to the description of the snapshot.fetch.size property for the MySQL connector to caution users that changing the default value can impair performance:

Jakub Čecháček: We might want to highlight in the docs for MySQL the impact of snapshot fetch size

Jakub Čecháček: Turns out using anything but default has a significant perf hit

Jakub Čecháček: No matter the value, row-by-row streaming is about 50% faster than using any batch size