Executing Linux solely on swap memory only
Executing Linux solely on swap memory only
Yes, it's feasible to run Linux using only swap and no physical RAM. It may become quite sluggish, but employing a high-performance SSD RAID setup could make the experience much smoother.
In theory it's possible to start a system without RAM, but it really depends on how the operating system is built. You'd need a motherboard firmware that doesn't depend on RAM during startup, and you'd have to set up the CPU and cache like RAM, perhaps using writeback mode. The OS would also have to be adjusted for this unusual setup, which could be seen as unfair since it still uses memory-like behavior. Linux might not work well here due to its large kernel size. It's probably wiser to create your own basic OS, choose a compatible PC, and install coreboot along with custom motherboard firmware. This approach works best for x86 systems, but other platforms—like embedded devices—can use alternative memory solutions such as microcontrollers. Since x86 has a fixed address map at boot, you could attempt building your own OS in that area, especially if the memory controller is ready before initialization.
Challenges are usually exciting, though this one seems a bit unusual. People have already discussed the technical aspects.