Rendezvous (Plan 9)
Encyclopedia
Rendezvous is a data synchronization
mechanism in Plan 9 from Bell Labs
. It is a system call
that allows two processes
to exchange a single datum while synchronizing.
The rendezvous call takes a tag and a value as its arguments. The tag is typically an address in memory shared by both processes. Calling rendezvous causes a process to sleep until a second rendezvous call with a matching tag occurs. Then, the values are exchanged and both processes are awakened.
More complex synchronization mechanisms can be created from this primitive operation. See also mutual exclusion
.
Data synchronization
Data synchronization is the process of establishing consistency among data from a source to a target data storage and vice versa and the continuous harmonization of the data over time. It is fundamental to a wide variety of applications, including file synchronization and mobile device...
mechanism in Plan 9 from Bell Labs
Plan 9 from Bell Labs
Plan 9 from Bell Labs is a distributed operating system. It was developed primarily for research purposes as the successor to Unix by the Computing Sciences Research Center at Bell Labs between the mid-1980s and 2002...
. It is a system call
System call
In computing, a system call is how a program requests a service from an operating system's kernel. This may include hardware related services , creating and executing new processes, and communicating with integral kernel services...
that allows two processes
Process (computing)
In computing, a process is an instance of a computer program that is being executed. It contains the program code and its current activity. Depending on the operating system , a process may be made up of multiple threads of execution that execute instructions concurrently.A computer program is a...
to exchange a single datum while synchronizing.
The rendezvous call takes a tag and a value as its arguments. The tag is typically an address in memory shared by both processes. Calling rendezvous causes a process to sleep until a second rendezvous call with a matching tag occurs. Then, the values are exchanged and both processes are awakened.
More complex synchronization mechanisms can be created from this primitive operation. See also mutual exclusion
Mutual exclusion
Mutual exclusion algorithms are used in concurrent programming to avoid the simultaneous use of a common resource, such as a global variable, by pieces of computer code called critical sections. A critical section is a piece of code in which a process or thread accesses a common resource...
.
External links
- Process Sleep and Wakeup on a Shared-memory Multiprocessor by Rob Pike, Dave Presotto, Ken Thompson and Gerard Holzmann.