Re: We need a new metric
I’m not sure you are understanding the roles of RAM & Storage.
RAM is volatile so when you turn the power off it’s gone. RAM is a fast cache for delivering data to the cpu, it’s more expensive than storage.
Storage on disk / tape etc is retained when the power is off, this is where you store your files for later retrieval, storage is cheaper than RAM.
Storage is normally far slower to read and write from than RAM so to do things efficiently with fast CPU’s you need that faster cache of the information you need to deliver so its copied into RAM for the cpu to work with.
Pre SSD’s, fast hard drives may have delivered ~100MBs, they could be pooled into array’s with data stripped on multiple disks so faster data rates where possible, a good sized array in a server or storage array delivering 1GBs was expensive but useful for purposes that needed it.
A cheap ssd today will deliver ~1GBs
Biggest question really is what you need all that RAM for and why 8GB isn’t enough. If an app consumes 1GB of RAM chances are most of the data isn’t used and only a fraction is needed, it’s more likely the app needs the data in your work file stored in RAM and again likely only a fraction of that data is actually worked on so that tiny fraction can easily be stored in RAM with the remainder of the app and its data on disk, so you only need a fraction of that 8GB of RAM to do work.
The penalty of reading from disk is time taken to do so, reading 8GB is less than 3 seconds on a modern m system but not all 8GB needs read/written so 1GB would be ~ 0.3s
If you have apps that need to read/write huge volumes from RAM & they absolutely need to be in RAM then it’s likely a portable computer isn’t what you need and a desktop like a Mac Pro or Mac Studio is most appropriate.
They demoed m1 Mac laptops editing multiple 4k streams in realtime which is far beyond what most people would do with their machines.
In summary
RAM is really high speed cache of data & instructions stored on disk & keeps the CPU running more efficiently instead of constantly waiting whilst it reads / writes from disk. If disk could be read/written as fast as RAM there would be no need for RAM
Current memory management methodologies mean there is little to no impact of paging to disk, case in point how long does it take for you to click in a different application and start to do work? Also paging to disk means os can address vastly more RAM than it has onboard by using page files.
Lastly Basic modern ssd ~3.2GBs storage as found in Mac’s is ~ half as fast as slow ddr3 ~6.4GBs from 2007