Question: At what certain amount of deleted post will cause a permaban? I lost count because I delete all this notification on my message because it's already annoying at that time.
There isn't a certain number of post deletion to necessitate a ban. Rather, there are steps that could walk you all the way to being ban permanently should you not pay heed to warning through series of temporal bans.
Spams aren't measured same way as plagiarism but, it is an offence non the less an not just on bitcointalk but, on any platform you might find yourself. With a reputation to keep, bitcointalk is devoted to keep a healthy forum and safe place for people to go about cryptocurrency discussions and transactions in between.
Hence, action certain rules is necessary. Here is what applies to spam related bans.
First offence: 7 days
Second offence: 14 days
Third offence: 30 days
Fourth: Permanent ban
Your first ban is your first warning. If you have to be banned for a fourth time it is permanent and you will no longer be allowed to participate on the forum under any accounts. Note: If you are banned on one account then you are not allowed to post under any accounts you own for the duration of your ban. The only exception to this rule is Meta where you can discuss the circumstances of your ban if you wish to do so but anywhere outside of that sub will be considered ban evasion and will get your ban doubled, but it is generally best to just patiently wait out your ban and improve your posts on return and hopefully no further bans will be needed.
As such, you've been given your first warning as a deterrent from such habits, you've got 2 more chances to amend else, you be hit with the fourth and that will be the stroke that settles the scores.