#14414: Profiled program runs 2.5x faster than non-profiled -------------------------------------+------------------------------------- Reporter: Fuuzetsu | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.2.1 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 Fuuzetsu): I don't know what you could be missing. I removed LLVM. I'm on i7 6770k, 64GB RAM, SSD. {{{ [shana@lenalee:/tmp]$ ghc --make -ddump-simpl -ddump-to-file -fforce- recomp -O2 -XBangPatterns -threaded -rtsopts -XOverloadedStrings fasta.ghc-2.hs -o fasta.ghc-2.ghc_run && ./fasta.ghc-2.ghc_run +RTS -N4 -s -RTS 250000 > /dev/null [1 of 1] Compiling Main ( fasta.ghc-2.hs, fasta.ghc-2.o ) Linking fasta.ghc-2.ghc_run ... 368,568,064 bytes allocated in the heap 15,735,800 bytes copied during GC 3,692,976 bytes maximum residency (7 sample(s)) 226,896 bytes maximum slop 9 MB total memory in use (0 MB lost due to fragmentation) Tot time (elapsed) Avg pause Max pause Gen 0 137 colls, 137 par 1.660s 1.660s 0.0121s 0.0280s Gen 1 7 colls, 6 par 0.127s 0.127s 0.0182s 0.0274s Parallel GC work balance: 35.73% (serial 0%, perfect 100%) TASKS: 10 (1 bound, 9 peak workers (9 total), using -N4) SPARKS: 0 (0 converted, 0 overflowed, 0 dud, 0 GC'd, 0 fizzled) INIT time 0.000s ( 0.000s elapsed) MUT time 0.206s ( 0.206s elapsed) GC time 1.787s ( 1.787s elapsed) EXIT time 0.000s ( 0.007s elapsed) Total time 1.993s ( 2.000s elapsed) Alloc rate 1,789,756,100 bytes per MUT second Productivity 10.3% of total user, 10.7% of total elapsed gc_alloc_block_sync: 0 whitehole_spin: 0 gen[0].sync: 0 gen[1].sync: 0 [shana@lenalee:/tmp]$ ghc --make -ddump-simpl -ddump-to-file -prof -fprof- auto -fforce-recomp -O2 -XBangPatterns -threaded -rtsopts -XOverloadedStrings fasta.ghc-2.hs -o fasta.ghc-2.ghc_run && ./fasta.ghc-2.ghc_run +RTS -N4 -s -p -RTS 250000 > /dev/null [1 of 1] Compiling Main ( fasta.ghc-2.hs, fasta.ghc-2.o ) Linking fasta.ghc-2.ghc_run ... 653,685,432 bytes allocated in the heap 42,865,544 bytes copied during GC 4,548,264 bytes maximum residency (9 sample(s)) 584,024 bytes maximum slop 10 MB total memory in use (0 MB lost due to fragmentation) Tot time (elapsed) Avg pause Max pause Gen 0 256 colls, 256 par 0.371s 0.371s 0.0014s 0.0073s Gen 1 9 colls, 8 par 0.015s 0.015s 0.0017s 0.0063s Parallel GC work balance: 16.49% (serial 0%, perfect 100%) TASKS: 10 (1 bound, 9 peak workers (9 total), using -N4) SPARKS: 0 (0 converted, 0 overflowed, 0 dud, 0 GC'd, 0 fizzled) INIT time 0.000s ( 0.000s elapsed) MUT time 0.487s ( 0.487s elapsed) GC time 0.386s ( 0.386s elapsed) RP time 0.000s ( 0.000s elapsed) PROF time 0.000s ( 0.000s elapsed) EXIT time 0.000s ( 0.001s elapsed) Total time 0.874s ( 0.874s elapsed) Alloc rate 1,340,938,477 bytes per MUT second Productivity 55.8% of total user, 55.8% of total elapsed gc_alloc_block_sync: 0 whitehole_spin: 0 gen[0].sync: 0 gen[1].sync: 0 }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14414#comment:4 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler