In this blog, I mostly write about performance issues (and tools to resolve them). I’d like to make a post about performance non-issues for a change. I think it might be interesting for two reasons. One, if not identified early, non-issues can consume lots of resources in terms of developers’ efforts, may introduce instability to the code and even cause the very performance issues they were supposed to prevent. Two, such non-issues usually reveal actual issues, even though those actual issues are mostly related to non-technical aspects of work, such as communication. I’ll start with a rather specific category of non-issues: when performance doesn’t match expectations because expectations don’t match reality.