An Old Netbook Spills Its Secrets [Hackaday]
For a brief moment in the late ’00s, netbooks dominated the low-cost mobile computing market. These were small, low-cost, low-power laptops, some tiny enough to only have a seven-inch display, and usually with extremely limiting hardware even for the time. There aren’t very many reasons to own a machine of this era today, since even the cheapest of tablets or Chromebooks are typically far more capable than the Atom-based devices from over a decade ago. There is one set of these netbooks from that time with a secret up its sleeve, though: Phoenix Hyperspace.
Hyperspace was envisioned as a way for these slow, low-power computers to instantly boot or switch between operating systems. [cathoderaydude] wanted to figure out what made this piece of software tick, so he grabbed one of the only netbooks that it was ever installed on, a Samsung N210. The machine has both Windows 7 and a custom Linux distribution installed on it, and with Hyperspace it’s possible to switch almost seamlessly between them in about six seconds; effectively instantly for the time.
[cathoderaydude]’s investigation into how bargain-basement hardware from 15 years ago is able to do this revealed more mysteries than it seemed to solve at the time. At first it looked like Hyperspace was acting as a hypervisor, essentially supervising the virtualization of both operating systems and switching between the two. But that’s not exactly what was going on here. Both operating systems seemed to share a partition and filesystem, certainly impossible, and it eventually he found a master boot record and file system hidden away at the end of the drive. From there he was able to piece together that a few different instances of GRUB were allowing all kinds of unusual things to happen, effectively mounting both operating systems at the same time to the hard drive and mapping them both into memory in ways that are still not entirely transparent.
From an outside perspective, this seems relatively similar to the discovery of the fast inverse square root algorithm within Quake, or this other similar (yet fictional) scenario. [cathoderaydude] admits during the analysis of these tools that it seems like Phoenix created what is effectively a miracle, by software standards, that no one ended up wanting or using, which was eventually forgotten to time. And, if you missed this era in computing history, head over here to see some of the other things that were lost from these days.