performance-visualization

In jlfwong/speedscope#188, I introduced TextDecoder as a way of avoiding performance issues with building up a huge string slowly. There are ways to make the fallback path faster and use less memory as well:

From @evanw:

The problem is that JavaScript JITs such as V8 optimize repeated string appends by building up a linked list in memory and only constructing the

fortio has so many features that -h or the README.md or the web UI are not making for an easy onboarding or discovery of all it can do and how to best use it

default values of many flags too (like now using -a -uniform -nocatchup being more or less required for serious use etc

for now I added these to https://github.com/fortio/fortio/wiki/FAQ#i-want-to-get-the-best-results-what-flags-sho

Bug: analyticalmonk/Rperform#44

Reference: ropensci/git2r#312