Simple .Net 9 Benchmark Comparisons

I was asked recently how to convert an integer representing a month to the quarter the month is in. Turns out the question was about performance, and my simple answer, use a simple (month - 1) / 3 + 1, which uses integer division and therefore should be very fast anyway, was not quite what was being looked for.

When pressed further I mentioned you could use a switch expression, but what they were looking for was to use a static array and do a simple lookup.

So on my way back home I thought about this, and decided to do a benchmark comparison. Always good to prove simple things like this for yourself 😉

How to Use

• Clone the repository
• Open the solution in VS Code
• launch.json and tasks.json are pre-configured to run the benchmarks
• Run and see the results in the Terminal window

Results

And here's the proof!

Method	Mean	Error	StdDev	Median	Allocated
MonthToQuarterUsingArray	8.562 ns	0.2031 ns	0.5278 ns	8.456 ns	-
MonthToQuarterUsingIntegerDivision	13.048 ns	0.2925 ns	0.3251 ns	12.963 ns	-
MonthToQuarterUsingSwitchExpression	32.312 ns	0.7340 ns	2.0940 ns	31.955 ns	-
MonthToQuarterUsingSwitchStatement	28.136 ns	0.9185 ns	2.6646 ns	27.422 ns	-