I'm getting to the point where I have a lot of email subscriptions running. Which is awesome! But it's also making me wonder about the mechanics of how things work.
Here is my assumption: When someone creates a new Topic or adds a Reply to an existing Topic, wpForo immediately sends out an email notification to everyone who is subscribed to that Topic. Is this correct or is there some kind of polling cron job that runs?
Assuming that my assumption is correct, does the Topic/Post wait to get saved into the database until all email notifications have been sent? If 100 people are subscribed, does this mean that the save could take a long time?
Are there SPAM concerns? Let's say that 500 people are subscribed to a Forum. When a new Topic is created, they will all get notified. But an email blast to 500 people can be an easy trigger for SPAM software to catch and block. Marketing solutions like MailChimp, etc. help to avoid this by sending emails in batches. Does wpForo send subscription email notifications in batches?
Keep in mind that wpForo just "sends" all email (outgoing smtp) to Wordpress core. wpForo doesn't actually send any email out.
So everything is handled by Wordpress standard email functions, so this is something you should take care with a plugin or an external service (if of cource you need so).
All email is send out in mass, as far as i know, from your Wordpress. That could create some problems, depending of your service hoster.
Personally, for my low needs with my tight hosting plan, i use a superb Queueing plugin and send everything from my hosting plan without any problems. All email is sent in batches that you configure via crons (the plugin does all that). Check out GD Mail Queue.
https://wordpress.org/plugins/gd-mail-queue/
I hope i've helped ...
Awesome! Thanks for the info.