what finally fixed our slow migration runs

we had a phpbb migration that looked fine in testing and then crawled in production. the import job was spending too much time on the same bottleneck, and it kept making the whole window unpredictable.

i worked through the process in smaller batches and watched where the time was actually going. once i tightened the import scope and reduced the amount of work happening in one pass, the run time settled down. that kept the rest of our deployment schedule from slipping.

less drama, fewer retries. if you are planning a migration, do not assume the first full run will tell you the whole story. are you importing attachments too, or just the post data?