Are modern CPUs really going to choke on a few thousand comparisons? My impression has always been that, for any constant-time operation, you're gonna need to

Are modern CPUs really going to choke on a few thousand comparisons? My impression has always been that, for any constant-time operation, you're gonna need to start getting into the 100Ks or even the millions to start noticing, but I don't have the data to back me up here :/