Guys do you how how long would it take to optimize 8tb with 12gb of ram
As others have explained, if using X-Plotter, there is no need to Optimise afterwards.
As for the time taken (with X-Plotter). It depends on several other factors, such as your Pc Cpu type (& cores) etc. Suggest Not to use All available Threads, since other processes may require some juice too.
If you run just one Plot for the whole 8Tb HDD, then it will probably take about 2½ days (± 12h). The risk is that, if there are any problems, you will need to run the whole process again. Alternatively, you could generate 2 or 3 or 4 (smaller) plots for the same drive, one after the other. (Just make sure that the Nonce-numbers don't overlap).
In my experience, Hard-Drives with more files take a little longer to scan while Mining, so it's a trade-off. But you're looking at (buffered) GPU plotting, so I'm not sure how useful this Nfo is.