#11284: Lambda-lifting fails in simple Text example -------------------------------------+------------------------------------- Reporter: bgamari | Owner: (none) Type: bug | Status: closed Priority: normal | Milestone: Component: Compiler | Version: 7.10.3 Resolution: duplicate | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Runtime | Unknown/Multiple performance bug | Test Case: Blocked By: | Blocking: Related Tickets: #5945, #11318 | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Changes (by sgraf): * keywords: LateLamLift => Comment: There's nothing to lift here anymore, all occuring functions turned into join points and the only actual let bindings in STG output are thunks, which can't be lifted. Here's an example run on `/usr/share/dict/words` (with an appropriate `main`): {{{ $ ./Main +RTS -s < /usr/share/dict/words 23 33,832,464 bytes allocated in the heap 24,088 bytes copied during GC 2,011,952 bytes maximum residency (2 sample(s)) 163,024 bytes maximum slop 1 MB total memory in use (0 MB lost due to fragmentation) Tot time (elapsed) Avg pause Max pause Gen 0 28 colls, 0 par 0.000s 0.000s 0.0000s 0.0000s Gen 1 2 colls, 0 par 0.000s 0.000s 0.0001s 0.0002s INIT time 0.000s ( 0.000s elapsed) MUT time 0.012s ( 0.012s elapsed) GC time 0.001s ( 0.000s elapsed) EXIT time 0.000s ( 0.000s elapsed) Total time 0.013s ( 0.013s elapsed) %GC time 0.0% (0.0% elapsed) Alloc rate 2,822,899,212 bytes per MUT second Productivity 95.0% of total user, 95.5% of total elapsed }}} Strange enough, the `Data.Text.Lazy` variant of this is much slower and allocates much more, when I actually thought it would cope better with `getContents`. Whatever, this doesn't seem relevant to LateLamLift anymore. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11284#comment:19 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler