ram, disc and thanos queries

[Thomas Will]

Hello experts, I am trying my best to clear these doubts, but getting stuck in them again and again. Can anyone please clear these.
1) For the period of time, the data is in Ram, that same ram data will not be present on disc at the same time? Example:- Assuming my Prometheus server just started, and it does 3 scraping rounds, the data is present in ram, will that data be present in the disc as well at the same time or not?

2) As I have read somewhere that 'For at most 2h data will be present in ram, and then will send it to disc'. Does that mean for 6 hrs, we will be writing to disc only 3 times?

3) The moment disc gets the data, Thanos can start taking data from it and sending it to cloud storage, right? or will it wait for the retention time to be over and then take the data?

Thanks in Advance.