Editing L4 microkernel family (section)

=== L4/Fiasco ===
In parallel to the development of L4Ka::Hazelnut, in 1998 the Operating Systems Group TUD:OS of the TU Dresden started to develop their own C++ implementation of the L4 kernel interface, named L4/Fiasco. In contrast to L4Ka::Hazelnut, which allows no concurrency in the kernel, and its successor L4Ka::Pistachio, which allows interrupts in the kernel only at specific preemption points, ''L4/Fiasco'' was fully preemptible (with the exception of extremely short atomic operations) to achieve a low [[interrupt latency]]. This was considered necessary because L4/Fiasco is used as the basis of DROPS,<ref>{{cite web |url=http://os.inf.tu-dresden.de/drops/overview.html |title=DROPS – Overview |website=[[Dresden University of Technology]] |access-date=2011-08-10 |url-status=live |archive-url=https://web.archive.org/web/20110807170107/http://os.inf.tu-dresden.de/drops/overview.html |archive-date=2011-08-07}}</ref> a hard [[real-time computing]] capable operating system, also developed at the TU Dresden. However, the complexities of a fully preemptible design prompted later versions of Fiasco to return to the traditional L4 approach of running the kernel with interrupts disabled, except for a limited number of preemption points.