Important Replying Topic very slow due to Subscriptions

The task of replying a topic on my forum was very very slow.

After lots of research to solve the problem I realize that, when I disable the topic subscription (e-mail notifications), the problem was solved.

It seems to me that e-mail notifications are synchronous, i.e, the user is redirected to his recent reply only after Kunena sent all e-mails to all topic subscribers.

Could e-mail notifications be set as assynchronous?

This is a major issue on my installation as well, both when using phpmail from the server and when using a third party smtp service with reasonable performance.

I'm also seeing resulting multiple postings due to multiple submits due to this delay which also result in excessive emails being sent (200+ per submit)

Advise on how to clear out existing subscriptions would be also appreciated, I've manually cleared the subscriptions table, with the following test post still resulting in 200+ email subscription notifications being sent, I had also disabled the subscription options in the config and ensured that no users other than myself were set as moderators on the thread

Hello guys,

reported to DEVs, when they have time will look in your problem.

Regards

Thaks @quila!