Skip to content
GitLab
Projects Groups Topics Snippets
  • /
  • Help
    • Help
    • Support
    • Community forum
    • Submit feedback
  • Register
  • Sign in
  • GHC GHC
  • Project information
    • Project information
    • Activity
    • Labels
    • Members
  • Repository
    • Repository
    • Files
    • Commits
    • Branches
    • Tags
    • Contributor statistics
    • Graph
    • Compare revisions
    • Locked files
  • Issues 5.5k
    • Issues 5.5k
    • List
    • Boards
    • Service Desk
    • Milestones
    • Iterations
  • Merge requests 636
    • Merge requests 636
  • CI/CD
    • CI/CD
    • Pipelines
    • Jobs
    • Artifacts
    • Schedules
    • Test cases
  • Deployments
    • Deployments
    • Releases
  • Analytics
    • Analytics
    • CI/CD
    • Code review
    • Insights
    • Issue
    • Repository
  • Wiki
    • Wiki
  • Snippets
    • Snippets
  • Activity
  • Graph
  • Create a new issue
  • Jobs
  • Commits
  • Issue Boards
Collapse sidebar
  • Glasgow Haskell CompilerGlasgow Haskell Compiler
  • GHCGHC
  • Issues
  • #5226
Closed
Open
Issue created May 27, 2011 by dreixel@dreixel

<<loop>> with -threaded -feager-blackholing, but only sometimes

While benchmarking the performance of GHC's SMP parallelism, I ran into an issue where (rarely) a test would fail with <<loop>>. I tried hard to reduce this to a single file, which I am attaching to this report.

To reproduce, compile the program with --make -threaded -feager-blackholing -rtsopts -O1 and run multiple times with -Nm with m>=2. In my case, using N8 (on a machine with 8 cores), I once got the error after 35 tries, but sometimes it takes thousands of attempts. I'm also attaching a bash script to compile and run the test repeatedly.

Tested with current HEAD, built on a Intel Xeon E5320, "perf" settings without dynamic linking. But I think I also encountered this behavior in GHC 7.0.3.

Trac metadata
Trac field Value
Version 7.1
Type Bug
TypeOfFailure OtherFailure
Priority normal
Resolution Unresolved
Component Compiler
Test case
Differential revisions
BlockedBy
Related
Blocking
CC
Operating system
Architecture
To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information
Assignee
Assign to
Time tracking