2 ms·
> This is a great post showing why you have to measure the specific tasks you care about rather than relying on general assumptions. If anything it turns out i
by Veedrac 6y ago
> This is a great post showing why you have to measure the specific tasks you care about rather than relying on general assumptions.
If anything it turns out it's an argument that benchmarks mislead way too readily and first-principles arguments (which would quickly refute the idea of a 3.5x slowdown due to vector width) should always be used to double-check your working.
- Agingcoder 6y agoIndeed! This reminds of a fun issue I ran into years ago with simd code(gcc, linux) . I was experimenting with various vector sizes, and found significant slowdowns for some vector sizes. I was about to call it quits, as in 'well, I'll have to do things differently', when I realized it didn't make any sense. I double checked the actual values computed by the benchmark, which happened to be completely wrong. What I had actually found was a compiler bug !