#13246: hPutBuf issues unnecessary empty write syscalls for large writes -------------------------------------+------------------------------------- Reporter: nh2 | Owner: Type: bug | Status: new Priority: normal | Milestone: 8.2.1 Component: Runtime System | Version: 8.0.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Runtime | Unknown/Multiple performance bug | Test Case: Blocked By: | Blocking: Related Tickets: #13245 | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by nh2): I've extracted the relevant code into a simple-to-run-and-modify single file, so that we can play around with it without recompiling `base`: * [https://gist.github.com/nh2/4cd40c2a4b15bf056bcae87907773786#file-ghc- bug-13246-repro-hs Without fix] * [https://gist.github.com/nh2/4cd40c2a4b15bf056bcae87907773786#file-ghc- bug-13246-fix-hs With fix] -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13246#comment:1 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler