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Xelblade

In case it's hard to read, green is transistors (DDD), dark blue is clock speed (MHz), light blue is power (Watts), and purple is performance/clock (ILP) rate. ILP is instruction level parallelism, and I believe DDD is Double Diffused Drain...?

choutiy

The answer to the question in this slide is:

parallelism performance is more focused on latency than throughput. Although the dumb way of asking a 10-core processor to do the same at once will increase the throughput by a factor of 10 but not affect the latency, the ultimate goal of parallelism is to shorten the amount of time to finish a certain job, through better algorithms, work distribution and communications.

kayvonf

@choutiy: I'm not sure if I agree entirely. The four-core CPU in my laptop allows me to watch a video on YouTube, run MS Word, download from Netflix, and play a song in iTunes easily in parallel, but it doesn't reduce the time I get any of those things done in comparison to if I was running any one of those programs on its own on a single core processor.

While its true that a single task with ample sub-task parallelism may complete faster on a parallel machine, parallel execution of many tasks at once can actually slow down the time to task any one of those tasks.