I hear it over and over again, that import is too slow.
Import is not fast anywhere else either. It takes lots of resources to import/merge/verify data.
I think it makes sense to make it even slower (and safer) with cron jobs by using the following settings:
If you run the import cron every 5 min, can use:
mautic:import --limit=2500
If your freshly imported data will trigger segments to update, you should limit that as well:
mautic:segment:update --batch-limit=2000
If your 45.000 contacts start receiving emails, you might want to set your cron accordingly:
mautic:emails:send --message-limit=2000