Page 82 - Computer_Science_F5

(c) Transparent mode: Here, DMA Real-world applications of DMA:
transfers data only when the CPU DMA plays a critical role in various
is executing the instruction which everyday tasks: Chapter One: Computer architecture
does not require the use of buses. (a) High-speed network data transfers:
(d) Scatter-gather DMA: Useful for DMA is essential for efficient
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transferring non-contiguous data network card interactions, enabling
blocks in memory to a contiguous smooth data flow across networks.
location in the external device (b) Video and audio data streaming:
and vice versa. Imagine the waiter DMA ensures smooth streaming of
collecting ingredients from different video and audio content by managing
shelves in the kitchen (scatter) and data transfers between memory and
graphics/audio cards efficiently.
bringing them together for the chef
(gather) (c) Disk I/O operations: DMA
accelerates data transfer speeds

Benefits of DMA Technology between storage devices and
memory, improving hard drive and
(a) Improved performance: Reduced disk operation efficiency.
processor involvement in data (d) Scientific computing: DMA is
transfers translates to faster data crucial for data-intensive scientific
movement between memory and computing applications, ensuring
external devices, leading to a fast and efficient transfer of large
noticeable performance boost for datasets.
tasks like video streaming and disk
I/O operations. (e) Real-time data processing: Real-
time processing systems rely on
(b) Increased system throughput: DMA to handle high volumes of
Processors remain free to handle data transfers effectively.
other tasks while DMA manages data
transfers, resulting in higher overall
system throughput. Imagine the Exercise 1.16
chefs in the restaurant being able to
prepare more dishes simultaneously 1. DMA allows direct memory
because the waiter efficiently handles access, bypassing the processor’s
deliveries. cache. How might this impact data

(c) Reduced processor load: Offloading consistency between the processor
data transfer responsibilities from and memory? Propose potential
the processor allows it to focus on solutions to mitigate this challenge.
core computational tasks and reduces 2. While DMA offers performance
overall workload. benefits, it adds hardware

73
Student’s Book Form Five

Computer Science Form 5.indd 73 23/07/2024 12:32