Aha. I believe that the ghc-7.10 branch simply doesn't have the source file testsuite/tests/perf/compiler/T9961.hs but all.T still runs the test. So we get "does not exist: T9961.hs", and of course very little allocation. Austin or Herbert, could you add T9961.hs to the 7.10 branch? Simon | -----Original Message----- | From: ghc-devs [mailto:ghc-devs-bounces@haskell.org] On Behalf Of | Herbert Valerio Riedel | Sent: 30 January 2015 11:03 | To: ghc-devs | Subject: 76-fold regression GHC 7.10->7.11 in T9961 byte-allocation | | Hello *, | | I noticed something odd while validating the GHC 7.10 branch: | | bytes allocated value is too low: | (If this is because you have improved GHC, please | update the test so that GHC doesn't regress again) | Expected T9961(normal) bytes allocated: 772510192 +/-5% | Lower bound T9961(normal) bytes allocated: 733884682 | Upper bound T9961(normal) bytes allocated: 811135702 | Actual T9961(normal) bytes allocated: 9766160 | Deviation T9961(normal) bytes allocated: -98.7 % | *** unexpected stat test failure for T9961(normal) | | | ...then I also ran ./validate against today's GHC HEAD, and re-ran the | T9961 test: | | Expected T9961(normal) bytes allocated: 772510192 +/-5% | Lower bound T9961(normal) bytes allocated: 733884682 | Upper bound T9961(normal) bytes allocated: 811135702 | Actual T9961(normal) bytes allocated: 748225848 | Deviation T9961(normal) bytes allocated: -3.1 % | | | I'm not sure if it's just the test-case being broken, or there's | something real regression between 7.10 and HEAD... | | However, I don't have time to investigate this. | | Cheers, | hvr | _______________________________________________ | ghc-devs mailing list | ghc-devs@haskell.org | http://www.haskell.org/mailman/listinfo/ghc-devs