This gist lists various C++ 'quick benchmarks' that have been written on quick-bench.com to test/verify various hypotheses. Quick Bench makes use of Google Benchmark.
Reserve in a vector vs not reserve
Cost of data indirection (e.g. direct vs pointer vs pointer-to-pointer)
Cost of using std::function
vs lambda and function pointers
Cost of using an std::set
for building a list of unique items vs using a std::vector
Applying pre-multiplied alpha to a 1024x1024 image
Lookup of a string key in a key-value container (attempting to run the test for different container sizes)
Populate vectors, maps, etc with data
Add/remove pointers from a vector or list (and assuming we need to find the item to remove in the vector)
Allocating memory on stack vs on heap (including dynamic size on stack)
Accessing a global static variable vs a local static variable vs a mutex-protected variable