NewRegressionFramework
From gem5
We'd like to revamp the regression tests by moving to a new framework. This page is intended to host a discussion of features and design for the new framework.
Desirable features
- Ability to add regressions via EXTRAS
- For example, move eio tests into eio module so we don't try to run them when it's not compiled in
- Ability to not run regressions for which binaries or other inputs aren't available
- With maybe some nice semi-automated way of downloading binaries when they're publicly available
- Better categorization of tests, and ability to run tests by category, e.g.:
- by CPU model
- by ISA
- by Ruby protocol
- by length
- More directed tests that cover specific functionality and complete faster. Running spec benchmarks is important but spends a lot of time doing the same thing over and over. Those should only be a component of our testing, not almost all of it like it is now. This is a desirable feature of our testing strategy, not necessarily something that impacts the regression framework.
- Better checkpoint testing
- some of this doesn't really depend on the regression framework, just needs new tests
- e.g., integrating util/checkpoint-tester.py
- Support for random testing (e.g., for background testing processes)
- Random latencies?
- Random testing a la memory testers but with different seeds, longer intervals
- Decouple from SCons somewhat
- Avoid having scons dependency bugs force unnecessary re-running of tests, particularly for update-refs
- Easy support for running separate tests where only the input parameters differ
- For example, several protocols utilize different state transitions depending on configuration flags. It would be great if we could test these without having to create new directories and tests.
- Similarly, we could/should test topologies this way as well.
- Automated way to use nightly regressions as a basis for updating "m5-stable"
- How do you identify the last working revision? (from Ali)
- Maybe need a bug-tracking system so we could record facts like "changeset Y fixes a bug introduced in changeset X" then we could automatically exclude changesets between X and Y, but we don't have that. (from stever)
- Better definitions of success criteria.
- E.g. Stats were changed, but output is all still correct vs simply passed and failed. (Passed, stats diffs, failed)
- For example you could say that the terminal output changing is fail, or the stdout and spec binary outputs changing are failed, but a 1% difference in stats is a stats difference, which needs to be addresses
- I envision this as providing reasonable certainty that if you create a change you know will modify the stats, you have a quick verification that nothing broke horribly before updating the stats.
Implementation ideas
Just ideas... no definitive decisions have been made yet.
- Use Python's unittest module, or something that extends it such as nose
- Use SCons to manage dependencies between binaries/test inputs and test results, but in a different SCons invocation (i.e., in its own SConstruct/SConscript)