Operating systems. # Types of Operating Systems ## Library Operating Systems AKA "Unikernel". These types of OSes are designed to be compiled into a single unikernel with their "applications" into a single file typically with a shared address space. This allows applications to be written with many of the advantages of coding with the support of an OS but then deployed onto bare metal with less overhead and only the features required by the application. > A unikernel is a specialised, single address space machine image constructed by using library operating systems.[1] A developer selects, from a modular stack, the minimal set of libraries which correspond to the OS constructs required for the application to run. These libraries are then compiled with the application and configuration code to build sealed, fixed-purpose images (unikernels) which run directly on a hypervisor or hardware without an intervening OS such as Linux or Windows. > > The first such systems were Exokernel and Nemesis in the late 1990s. The term "library operating system" has been around since at least 1995 when it was used in the [[Exokernel]] [research paper](https://dl.acm.org/doi/abs/10.1145/224057.224076). According to Google Trends it seems that interest in the term "library operating system" has been steadily declining since it began storing trend data in 2004. From my own experience there was a short spike of buzz around the term in 2017, likely tied to the startup behind [[IncludeOS]]. The term "unikernel" had been floating around since at least 1990 (with some uses in the 70s in mathematics papers), but the meaning (and Google trend data) stabilized after 2013 after the release of the [[Mirage OS]] paper. # Resources ```cardlink url: https://en.wikipedia.org/wiki/Unikernel title: "Unikernel - Wikipedia" host: en.wikipedia.org favicon: /static/favicon/wikipedia.ico image: https://upload.wikimedia.org/wikipedia/commons/b/b3/Unikernel_mirage_example.png ``` ```cardlink url: https://www.sigarch.org/leave-your-os-at-home-the-rise-of-library-operating-systems/ title: "Leave your OS at home: the rise of library operating systems" description: "The efficiency of Operating Systems (OSes) has always been in the spotlight of systems researchers, ever since the seminal Dijkstra’s THE multiprogramming system in early 60s. But the reason …" host: www.sigarch.org favicon: https://www.sigarch.org/wp-content/uploads/2020/06/sigarchfavicon316-150x150.png image: https://www.sigarch.org/wp-content/uploads/2017/09/Fotolia_122527508_Subscription_Monthly_M.jpg ``` ```cardlink url: https://queue.acm.org/detail.cfm?id=2566628 title: "Unikernels: Rise of the Virtual Library Operating System - ACM Queue" host: queue.acm.org ``` ```cardlink url: https://www.microsoft.com/en-us/research/publication/rethinking-the-library-os-from-the-top-down/ title: "Rethinking the Library OS from the Top Down - Microsoft Research" description: "This paper revisits an old approach to operating system construction, the library OS, in a new context. The idea of the library OS is that the personality of the OS on which an application depends runs in the address space of the application. A small, fixed set of abstractions connects the library OS to the […]" host: www.microsoft.com ``` ## Hobby ```cardlink url: https://www.osnews.com/story/24405/hobby-os-deving-3-designing-a-kernel/ title: "Hobby OS-deving 3: Designing a Kernel – OSnews" host: www.osnews.com favicon: https://www.osnews.com/icons/favicon-32x32.png ``` ```cardlink url: https://www.osnews.com/story/1385/comparing-menuetos-skyos-and-atheos/ title: "Comparing MenuetOS, SkyOS and AtheOS – OSnews" host: www.osnews.com favicon: https://www.osnews.com/icons/favicon-32x32.png ``` # Lists - https://vintageos.org/others.html