What is the practical purpose of the
first_lifetime setting for Magento 2's Redis session storage? The Magento documentation notes:
Lifetime, in seconds, of session for non-bots on the first write, or use 0 to disable.
Is this intended to just prevent session storage from being eaten up by users who bounce?
The challenge is that this effectively turns into a timeout for checkout, because no matter many pages a user has hit on their way to checkout, every load to the checkout controller counts as a "first write" because the core controller resets the session ID. (This trumps any general session lifetime setting configured for the site.) If the purpose of the setting is just to protect cache storage from being wasted, this potential damage to conversions is too high a price, especially at the default setting of 10 minutes.