Amoeba (operating system)

From Wikipedia, the free encyclopedia
Jump to: navigation, search
Developer Andrew S. Tanenbaum
Latest release 5.3 / 30 July 1996; 20 years ago (1996-07-30)[1]
Available in English
Platforms i386/i486, MIPS, Motorola 68030, NS 32016, Sun 3/50 and 3/60, SPARC, VAX
Kernel type Microkernel
License MIT license[2]
Official website

Amoeba is a distributed operating system developed by Andrew S. Tanenbaum and others at the Vrije Universiteit Amsterdam. The aim of the Amoeba project was to build a timesharing system that makes an entire network of computers appear to the user as a single machine. Development at the Vrije Universiteit was stopped: the source code of the latest version (5.3) were last modified on 30 July 1996.[1]

The Python programming language was originally developed for this platform.[3]


The goal of the Amoeba project was to construct an operating system for networks of computers that would present the network to the user as if it were a single machine. An Amoeba network would consist of a number of workstations connected to a "pool" of processors, and executing a program from a terminal would cause it to run on any of the available processors, with the operating system providing load balancing.[4] Unlike the contemporary Sprite, Amoeba did not support process migration.[5] The workstations would typically function as networked terminals only. Aside from workstations and processors, additional machines would operate as servers for files, directory services, TCP/IP communications etc.[4]

Amoeba was a microkernel-based operating system. It offered multithreaded programs and a remote procedure call (RPC) mechanism for communication between threads, potentially across the network; even kernel-threads would use this RPC mechanism for communication. Each thread was assigned a 48-bit number called its "port", which would serve as its unique, network-wide "address" for communication.[4]

The user interface and APIs of Amoeba were modeled after Unix and compliance with the POSIX standard was partially implemented; some of the Unix emulation code consisted of utilities ported over from Tanenbaum's other operating system, MINIX. Early versions used a "homebrew" window system, which the Amoeba authors considered "faster ... in our view, cleaner ... smaller and much easier to understand", but version 4.0 used X (and allowed X terminals as terminals).[4]

The system used FLIP as a network protocol.

See also[edit]


  1. ^ a b "Amoeba FTP". 
  2. ^ [1]
  3. ^ "Why was Python created in the first place?". Python FAQ. Archived from the original on 23 February 2008. Retrieved 2008-02-11. 
  4. ^ a b c d Andrew S. Tanenbaum, M. Frans Kaashoek, Robbert van Renesse and Henri E. Bal (1991). The Amoeba distributed operating system — a status report. Computer Communications 14.
  5. ^ Fred Douglis, M. Frans Kaashoek, Andrew S. Tanenbaum and John Ousterhout (1991). A comparison of two distributed systems: Amoeba and Sprite. Computing Systems 4(4), pp. 353–384.

External links[edit]