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sarchlab / mgpusim

A highly-flexible GPU simulator for AMD GPUs.
MIT License
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unified-gpu and unified-memory flags #107

Open Soilorian opened 2 days ago

Soilorian commented 2 days ago

Hello Mr. Sun,

I hope you’re doing well.

I’ve been working with the simulator and encountered some confusion while testing the flags. I’m having trouble fully understanding their specific functions. Could you explain in a bit more detail what each flag does and what the effect is when both are used together?

During my tests, I monitored the page migrations and the GPU count throughout execution. When I ran the command below with both flags enabled:

./fir -timing -use-unified-memory -unified-gpus=1,2,3,4

I noticed that there were no page migrations, and the GPU count registered as only 1.

Thank you for your help!

syifan commented 2 days ago

-unified-gpus allows the memory to be allocated evenly on these GPUs and threads be distributed evenly on these GPUs. -use-unified-memory allows page migration. There may be no migration if the pages are perfectly aligned. I need more information about how you noticed no page migration and GPU count registered as 1. At which line, which variable did you get your observation?