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Figure 4. | Dual Path Bus Implementation |
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Without a dual path bus, there is often contention for system resources such as main memory. When contention between the processor and a bus master occurs, one has to wait for the other to finish its memory cycle before it can proceed. Thus, fast devices like processors have to wait for much slower I/O devices, slowing down the performance of the entire system to the speed of the slowest device. This is very costly to the overall system performance.
1.3.4 SynchroStream Technology
SynchroStream is an extension of the dual bus path technique. The SynchroStream controller synchronizes the operation of fast and slow devices and streams data to these devices to ensure that all devices work at their optimum levels of performance.
It works much like a cache controller in that it
When devices are writing data into memory, the IBM SynchroStream controller again buffers the data, and writes it to memory after the bus cycle is complete.
Since devices are not moving data to and from memory directly, but to the SynchroStream controller, each device has its own logical path to memory. The devices do not have to wait for other, slower devices.
8NetWare Integration Guide
