#15938: Hadrian's recompilation check is extremely slow -------------------------------------+------------------------------------- Reporter: bgamari | Owner: (none) Type: bug | Status: new Priority: high | Milestone: 8.8.1 Component: Build System | Version: 8.6.2 (Hadrian) | Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by alpmestan): @snowleopard: Ben reported the following to me in private: - when re-running hadrian the second time with `-VVV`, Ben saw: {{{ | Building Stage1 libraries: binary, Cabal, ghc, ghc-boot, ghc-boot- th, ghc-heap, ghci, hpc, mtl, parsec, template-haskell, text, transformers, terminfo, array, base, bytestring, containers, deepseq, directory, filepath, ghc-compact, ghc-prim, haskeline, integer-gmp, pretty, process, rts, stm, time, xhtml, libiserv, unix | Building Stage1 programs : ghc, ghc-pkg, hsc2hs, unlit, hpc, ghc- iserv, runghc # _build/stage1/lib/package.conf.d/ghc-8.7.conf # _build/stage1/lib/package.conf.d/Cabal-2.4.0.1.conf # _build/stage1/lib/package.conf.d/ghci-8.7.conf # _build/stage2/bin/ghctags # _build/stage2/bin/haddock # _build/stage1/lib/package.conf.d/text-1.2.3.1.conf # _build/stage1/lib/package.conf.d/parsec-3.1.13.0.conf # _build/stage1/lib/bin/ghc-iserv # _build/stage1/bin/hsc2hs # _build/stage1/bin/ghc # _build/stage1/lib/package.conf.d/haskeline-0.7.4.3.conf # _build/stage1/lib/package.conf.d/libiserv-8.7.1.conf # _build/stage1/bin/ghc-pkg # _build/stage0/lib/package.conf.d/directory-1.3.1.5.conf }}} and it just pauses there for ~15 seconds before it finally starts issuing build commands. - using -j16 or -j1 doesn't seem to affect the "pause" time -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15938#comment:4 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler