That depends entirely on the kind of performance delta we're talking about.
If a particular testcase went from actually hanging (endless loop, or running for hours) to finishing quickly (say, in 1 millisecond), then by all means land that testcase. (You don't have to detect the hang yourself, the test driver already has a timeout for each test.) Ideally you're spending your time on changes that visibly improve one of the major benchmarks we're tracking anyway. In that case, there's no need to add a separate performance test; but please do add correctness tests for the feature you're adding/modifying. Other than that we usually don't have fine-grained performance tests. Optimizing for micro-benchmarks is easy but often pointless. Also, it's important to realize that the test suite is supposed to assert correctness while finishing as quickly as possible, whereas measuring performance typically requires running the tests in question for a considerable amount of time to get reliable results. On Thu, Sep 25, 2014 at 4:19 PM, Isiah Meadows <[email protected]> wrote: > How's the best way to test for a performance regression (as in "this test > should not hang")? > On Sep 23, 2014 1:28 AM, "Ben Noordhuis" <[email protected]> wrote: > >> On Tue, Sep 23, 2014 at 1:48 AM, Isiah Meadows <[email protected]> >> wrote: >> > What I need to do for a specific unit test is to run a specific method + >> > arguments, and if it takes too long, stop the call mid-cycle and fail >> the >> > test. This is for a performance-related unit test for my patch (which >> is a >> > perf patch itself, anyways). Is this possible, and if so, how would I >> do it? >> > I'm not nearly as well versed in C++ as I am in JavaScript, but I could >> > write it in C++ if I had to. >> >> It sounds like you would need to call V8::TerminateExecution() from a >> watchdog thread. That said, tests that rely on wall clock time are >> unreliable and will almost certainly get rejected during code review. >> >> -- >> > -- -- v8-users mailing list [email protected] http://groups.google.com/group/v8-users --- You received this message because you are subscribed to the Google Groups "v8-users" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
