Re:AMD Ryzen Threadripper 3000 32-core CPU is more bad news ...
by d33 on Friday September 20, 2019 @06:03PM
(#21031773)
Interesting! Is there a simple way to measure memory latency?
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Re:AMD Ryzen Threadripper 3000 32-core CPU is more bad news ...
by dragontamer on Saturday September 21, 2019 @03:05AM
(#21033952)
Create 1-billion 32-bit integers numbers between 0 to 1-billion. Knuth shuffle the integers.
"Linked list" traverse the integers as follows:
//array is full of 1-billion numbers, randomly sorted
uint32_t idx = 0;
for(int i=0; i<200000000; i++){
idx = array[idx]; // Random traversal
}
Pull out a stopwatch (or use Linux's "time" functionality). Divide the time by 200000000. You've now measured memory latency.
Re:AMD Ryzen Threadripper 3000 32-core CPU is more bad news ...
by dlemire on Saturday September 21, 2019 @05:47PM
(#21038108)
I suggest using Sattolo’ algorithm instead.
Here is a relevant blog post https://lemire.me/blog/2018/11/13/memory-level-parallelism-i...