Re: Cost of handling misaligned access

Michael S wrote:

On Thu, 6 Feb 2025 21:36:38 +0100
Terje Mathisen <terje.mathisen@tmsw.no> wrote:

BTW, when I timed 1000 calls to that 5-6 us program, to get around
teh 100 ns timer resolution, each iteration ran in 5.23 us.

 That measurement could be good enough on desktop. Or not.
It certainly not good enough on laptop and even less so on server.
On laptop I wouldn't be sutisfied before I lok my program to
particualr core, then do something like 21 measurements with 100K calls
in each measurement (~10 sec total) and report median of 21.

Each measurement did 1000 calls, then I ran 100 such measurements. The 5.23 us value was the lowest seen among the 100, with average a bit more:
Slowest: 9205200 ns
Fastest: 5247500 ns
Average: 5672529 ns/iter
Part1 = 3338
My own (old, but somewhat kept up to date) cputype program reported that it is a "13th Gen Intel(R) Core(TM) i7-1365U" according to CPUID.
Is that sufficient to judge the performance?
Terje
--
- <Terje.Mathisen at tmsw.no>
"almost all programming can be viewed as an exercise in caching"