diff options
| author | Matthew Pickering <matthewtpickering@gmail.com> | 2020-12-07 13:19:28 +0000 |
|---|---|---|
| committer | Marge Bot <ben+marge-bot@smart-cactus.org> | 2021-03-03 08:12:29 -0500 |
| commit | d89deeba47ce04a5198a71fa4cbc203fe2c90794 (patch) | |
| tree | 8f879bbb0774ce686e1688cc638ef22179babf51 /docs/users_guide | |
| parent | d8dc0f96237fe6fe7081c04727c7c2573477e5cb (diff) | |
| download | haskell-d89deeba47ce04a5198a71fa4cbc203fe2c90794.tar.gz | |
Profiling: Allow heap profiling to be controlled dynamically.
This patch exposes three new functions in `GHC.Profiling` which allow
heap profiling to be enabled and disabled dynamically.
1. startHeapProfTimer - Starts heap profiling with the given RTS options
2. stopHeapProfTimer - Stops heap profiling
3. requestHeapCensus - Perform a heap census on the next context
switch, regardless of whether the timer is enabled or not.
Diffstat (limited to 'docs/users_guide')
| -rw-r--r-- | docs/users_guide/9.2.1-notes.rst | 6 | ||||
| -rw-r--r-- | docs/users_guide/profiling.rst | 10 |
2 files changed, 15 insertions, 1 deletions
diff --git a/docs/users_guide/9.2.1-notes.rst b/docs/users_guide/9.2.1-notes.rst index 918f8ebae8..2630ae91fe 100644 --- a/docs/users_guide/9.2.1-notes.rst +++ b/docs/users_guide/9.2.1-notes.rst @@ -93,6 +93,12 @@ Compiler that the compiler automatically insert cost-centres on all call-sites of the named function. +- The heap profiler can now be controlled from within a Haskell program using + functions in ``GHC.Profiling``. Profiling can be started and stopped or a heap + census requested at a specific point in the program. + There is a new RTS flag :rts-flag:`--no-automatic-heap-samples` which can be + used to stop heap profiling starting when a program starts. + GHCi ~~~~ diff --git a/docs/users_guide/profiling.rst b/docs/users_guide/profiling.rst index 1eddcb7160..6eb5008146 100644 --- a/docs/users_guide/profiling.rst +++ b/docs/users_guide/profiling.rst @@ -459,7 +459,7 @@ compiled program. :type: dynamic Deprecated alias for :ghc-flag:`-fprof-auto-exported` - + .. ghc-flag:: -caf-all :shortdesc: *(deprecated)* Alias for :ghc-flag:`-fprof-cafs` :type: dynamic @@ -886,6 +886,14 @@ There are three more options which relate to heap profiling: profiles are always sampled with the frequency of the RTS clock. See :ref:`prof-time-options` for changing that. +.. rts-flag:: --no-automatic-heap-samples + + :since: 9.2.1 + + Don't start heap profiling from the start of program execution. If this + option is enabled, it's expected that the user will manually start heap + profiling or request specific samples using functions from ``GHC.Profiling``. + .. rts-flag:: -L ⟨num⟩ Sets the maximum length of a cost-centre stack name in a heap |