Single Address Space Operating Systems (SASOSs) are OSs in which all code and data exists within one, big, shared address space, often threaded. Using one address space facilitates and enhances sharing and cooperation, because it lets addresses have a unique (for all time) representation or interpretation. Thus, pointer-based data structures can be directly communicated and shared between programs at any time, and can be stored directly on secondary storage with no need to translate. Such structures are simplified by using larger address spaces. All earlier OSs were SASOSs, because computers only used single address spaces; that was all that existed, there was nothing else. Segmented/paged address spaces were a later development. Most present, common personal computers use the x86 architecture, which began as the segmented 8088/8086; though i386 and later IA32 processors have a single address space (flat) memory mode. Future, larger processors may return more to single address spaces a- Category ID : 60974
Orthogonally persistent, capability-based secure SASOS using L4 2nd generation microkernel. Goals: Prove SASOSs can run on normal hardware, be as secure as normal OSs; can be as efficient as, and are faster than, normal OSs in some important uses; can be pure SASOSs with all data (even system data) in one address space and no other IPC mechanism is supported by OS. POSIX emulating. [Open Source, GPL]
Exploring a new OS structure, tuned to the needs of complex applications (eg, CAD/CAM) where a number of cooperating programs manipulate a large shared persistent database of objects.
Where stale pointers make it hard to re-use addresses, some have claimed that a 64-bit address space is so big that there is no need to ever re-use addresses. Results of kernel-level tracing of department workstations.
Multitasking SASOS with transparent data persistence: users and application programmers need not know or care that system memory is transient and must be written to disk to persist across reboots, all details done by OS, so once data is made, it exists until explicitly destroyed, like physical objects. [Open Source, GPL]