- Branche: Computer
- Number of terms: 4807
- Number of blossaries: 1
- Company Profile:
Sun Microsystems is a multinational vendor of computers, computer software and hardware, and information technology services.
In the shared memory architecture, a mechanism for caches to communicate with each other as well as with main memory. In packet switching, traffic is divided into small segments called packets that are multiplexed onto the bus. A packet carries identification that enables cache and memory hardware to determine whether the packet is destined for it or to send the packet on to its ultimate destination. Packet switching allows bus traffic to be multiplexed and unordered (not sequenced) packets to be put on the bus. The unordered packets are reassembled at the destination (cache or main memory). See also cache, shared memory.
Industry:Computer
In the Java Message Service, an asynchronous request, report, or event that is created, sent, and consumed by an enterprise application and not by a human. It contains vital information needed to coordinate enterprise applications, in the form of precisely formatted data that describes specific business actions.
Industry:Computer
A J2EE component that implements a business task or business entity and is hosted by an EJB container; either an entity bean, a session bean, or a message-driven bean.
Industry:Computer
In the distributed memory architecture, a mechanism for processes to communicate with each other. There is no shared data structure in which they deposit messages. Message passing allows a process to send data to another process and for the intended recipient to synchronise with the arrival of the data.
Industry:Computer
A highly optimised Java runtime environment targeting a wide range of consumer products, including pagers, cellular phones, screen phones, digital set-top boxes, and car navigation systems.
Industry:Computer
In systems with multiple caches, the mechanism that ensures that all processors see the same image of memory at all times.
Industry:Computer
A hardware feature where operations are reduced to multiple stages, each of which takes (typically) one cycle to complete. The pipeline is filled when new operations can be issued each cycle. If there are no dependencies among instructions in the pipe, new results can be delivered each cycle. Chaining implies pipelining of dependent instructions. If dependent instructions cannot be chained, when the hardware does not support chaining of those particular instructions, then the pipeline stalls.
Industry:Computer
In multithreading, a situation where two or more threads simultaneously access a shared resource. The results are indeterminate depending on the order in which the threads accessed the resource. This situation, called a data race, can produce different results when a programme is run repeatedly with the same input. See also mutual exclusion, mutex lock, semaphore lock, single-lock strategy, spin lock.
Industry:Computer
A hardware feature of some pipeline architectures that allows the result of an operation to be used immediately as an operand for a second operation, simultaneously with the writing of the result to its destination register. The total cycle time of two chained operations is less than the sum of the stand-alone cycle times for the instructions. For example, the TI 8847 supports chaining of consecutive fadd, fsub, and fmul (of the same precision). Chained faddd/fmuld requires 12 cycles, while consecutive unchained faddd/fmuld requires 17 cycles.
Industry:Computer
In multitasking operating systems, such as the SunOStrademark operating system, processes run for a fixed time quantum. At the end of the time quantum, the CPU receives a signal from the timer, interrupts the currently running process, and prepares to run a new process. The CPU saves the registers for the old process, and then loads the registers for the new process. Switching from the old process state to the new is known as a context switch. Time spent switching contexts is system overhead; the time required depends on the number of registers, and on whether there are special instructions to save the registers associated with a process.
Industry:Computer
