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<p class="MsoNormal"><span lang="EN-US">Despite a recent <o:p></o:p></span></p>
<p class="Code"><span lang="EN-US">git fetch <a href="https://gitlab.haskell.org/ghc/ghc-performance-notes.git">
https://gitlab.haskell.org/ghc/ghc-performance-notes.git</a><o:p></o:p></span></p>
<p class="Code" style="text-indent:13.3pt"><span lang="EN-US">refs/notes/perf:refs/notes/ci/perf<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I’m getting lots of perf regressions in HEAD. For example<o:p></o:p></span></p>
<p class="Code"><span lang="EN-US">=====> T9203(normal) 1 of 1 [0, 0, 0]<o:p></o:p></span></p>
<p class="Code"><span lang="EN-US">]0;T9203(normal) 1 of 1 [0, 0, 0]cd "T9203.run" && "/home/simonpj/code/HEAD-3/inplace/bin/ghc-stage2" -o T9203 T9203.hs -dcore-lint -dstg-lint -dcmm-lint -no-user-package-db -rtsopts -fno-warn-missed-specialisations -fshow-warning-groups
-fdiagnostics-color=never -fno-diagnostics-show-caret -Werror=compat -dno-debug-output -O2<
<o:p></o:p></span></p>
<p class="Code"><span lang="EN-US">cd "T9203.run" && ./T9203 +RTS -V0 -tT9203.stats --machine-readable -RTS <
<o:p></o:p></span></p>
<p class="Code"><span lang="EN-US">runtime/bytes allocated increased from x86_64-linux-deb9 baseline @ HEAD~28:<o:p></o:p></span></p>
<p class="Code"><span lang="EN-US"> Expected T9203 (normal) runtime/bytes allocated: 56046952.0 +/-5%<o:p></o:p></span></p>
<p class="Code"><span lang="EN-US"> Lower bound T9203 (normal) runtime/bytes allocated: 53244604
<o:p></o:p></span></p>
<p class="Code"><span lang="EN-US"> Upper bound T9203 (normal) runtime/bytes allocated: 58849300
<o:p></o:p></span></p>
<p class="Code"><span lang="EN-US"> Actual T9203 (normal) runtime/bytes allocated: 108464536
<o:p></o:p></span></p>
<p class="Code"><span lang="EN-US"> Deviation T9203 (normal) runtime/bytes allocated: 93.5 %<o:p></o:p></span></p>
<p class="Code"><span lang="EN-US">*** unexpected stat test failure for T9203(normal)<o:p></o:p></span></p>
<p class="Code"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="Code"><span lang="EN-US">Performance Metrics (test environment: local):<o:p></o:p></span></p>
<p class="Code"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="Code"><span lang="EN-US">T9203(normal) runtime/bytes allocated 108464536.000<o:p></o:p></span></p>
<p class="Code"><span lang="EN-US"> (baseline @ HEAD~28) 56046952.000 [increased, 93.5%]<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">What am I doing wrong?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Simon<o:p></o:p></span></p>
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