address space


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address space

[′ad·rəs ‚spās]
(computer science)
The number of storage locations available to a computer program.

address space

(operating system, architecture)
The range of addresses which a processor or process can access, or at which a device can be accessed. The term may refer to either physical address or virtual address.

The size of a processor's address space depends on the width of the processor's address bus and address registers.

Each device, such as a memory integrated circuit, will have its own local address space which starts at zero. This will be mapped to a range of addresses which starts at some base address in the processor's address space.

Similarly, each process will have its own address space, which may be all or a part of the processor's address space. In a multitasking system this may depend on where in memory the process happens to have been loaded. For a process to be able to run at any address it must consist of position-independent code. Alternatively, each process may see the same local address space, with the memory management unit mapping this to the process's own part of the processor's address space.

address space

A computer's address space is the total amount of memory that can be addressed by the computer. The term may refer to the physical memory (RAM chips) or virtual memory (disk/SSD). For example, a 32-bit computer can address 4GB of physical memory and as much as 64TB of virtual memory. See address register and flat address space.
References in periodicals archive ?
So we allocated address space sort of like telephone numbers sufficient to define 4.
The institutions that control IP addresses internationally and in the Asia-Pacific region have depleted the IPv4 address space, and are promoting a transition to IPv6 with the World IPv6 Launch.
The rapid growth of global Internet users and an increasing need for unique IP addresses exhausted the address space about 30 years after the standardization of IPv4 in 1981
These plans included IPv6 addressing architecture and a model to cope with the exhaustion of the IPv4 address space.
In order to avoid projected address-space depletion, IPv4 systems must be transitioned to the newer IPv6 protocol, which has a vastly larger address space.
The latest data from the Regional Internet Registries, which are responsible for allocating address blocks to ISPs and large organizations, says that less than 18% of the total IPv4 address space available to them was allocated between January 1999 and June 2003.
While Okabe says that IPv6 is "necessary" for future development, solving address space, adding a plug-and-play function and enabling end-to-end communication, he sees difficulties in the short term because so many companies have investments in legacy systems with specialized protocols.
Similar to the ASU-1 Data Store, the User Store also has read write streams that are randomly distributed across the entire address space of the ASU.
Telecomms solutions provider Global Crossing has released a free Internet tool that can reportedly assist in the management and assignation of Internet Protocol address space.
Wylde indicated that the New York City Partnership & Chamber of Commerce, of which she is also President, is working closely with Assembly Speaker Sheldon Silver, Senate Majority Leader Joseph Bruno, the New York City Economic Development Corporation and the Empire State Development Corporation to develop a program that will address space needs in the City.
Since each server has its own address space, all these objects are protected from one another.
In fact, every couple of years the amount of memory address space needed to run whatever software is mainstream at the time just about doubles.