From b931fde9f5ad23e0ac7369146ee45615864f7193 Mon Sep 17 00:00:00 2001 From: Mark Date: Sun, 3 Jun 2018 22:40:29 -0500 Subject: [PATCH] add more on crater + perf runs --- src/tests/intro.md | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/src/tests/intro.md b/src/tests/intro.md index 7c3832ed..034b7aac 100644 --- a/src/tests/intro.md +++ b/src/tests/intro.md @@ -203,6 +203,23 @@ While crater is really useful, it is also important to be aware of a few caveats that the crate doesn't compile any more (e.g. used old nightly features), has broken or flaky tests, requires network access, or other reasons. +- Before crater can be run, `@bors try` needs to suceed. This means that if + your code doesn't compile or fails tests, you cannot run crater. + +## Perf runs + +A lot of work is put into improving the performance of the compiler and +preventing performance regressions. A "perf run" is used to compare the +performance of the compiler in different configurations for a large collection +of popular crates. Different configurations include "fresh builds", builds +with incremental compilation, etc. + +The result of a perf run is a comparison between two versions of the +compiler (by their commit hashes). + +You should request a perf run if your PR may affect performance, especially +if it can affect performance adversely. + ## Further reading The following blog posts may also be of interest: