Re: [GHC] #15136: High CPU when asynchronous exception and unblocking retry on TVar raced

#15136: High CPU when asynchronous exception and unblocking retry on TVar raced -------------------------------------+------------------------------------- Reporter: nshimaza | Owner: osa1 Type: bug | Status: merge Priority: highest | Milestone: 8.6.1 Component: Runtime System | Version: 8.4.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: Runtime crash | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D4956 Wiki Page: | -------------------------------------+------------------------------------- Comment (by Ben Gamari ): In [changeset:"502640c90c3d0fbb6c46257be14fdc7e3c694c6c/ghc" 502640c9/ghc]: {{{ #!CommitTicketReference repository="ghc" revision="502640c90c3d0fbb6c46257be14fdc7e3c694c6c" Optimise wakeups for STM Avoids repeated wakeup messages being sent when a TVar is written to multiple times. See comments for details. Test Plan: * Test from #15136 (will be added to stm shortly) * existing stm tests Reviewers: bgamari, osa1, erikd Reviewed By: bgamari Subscribers: rwbarton, thomie, carter GHC Trac Issues: #15136 Differential Revision: https://phabricator.haskell.org/D4961 }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15136#comment:15 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler