undocumented cost centres with -hd and -hy

[Sönke Hahn]

On Wednesday 10 March 2010 04:08:19 pm Thomas Schilling wrote:
> PAP stands for partial application, i.e., a function with one or more
> missing arguments.  MUT_ARR_PTRS_FROZEN are mutable objects which are
> not moved by the garbage collector.  They are an implementation detail
> of IORefs and mutable arrays (ST(U)Array, IO(U)Array, ...).  Before
> entering a suspended computation (a THUNK), GHC overwrites it with a
> BLACKHOLE, to avoid space leaks and to detect cyclic dependencies.
> 
> HTH

Yes, that does help, thanks.

> 
> On 10 March 2010 13:30, Soenke Hahn <shahn at cs.tu-berlin.de> wrote:
> > When using the heap profiling options -hd (profiling by closure
> > description) and -hy (profiling by type) there are some
> > compiler-generated cost centres, for example "PAP",
> > "MUT_ARR_PTRS_FROZEN" and "BLACKHOLE". I wasn't able to find
> > documentation on them. Is there any?
> > 
> > Thanks,
> > Sönke
> > _______________________________________________
> > Glasgow-haskell-users mailing list
> > Glasgow-haskell-users at haskell.org
> > http://www.haskell.org/mailman/listinfo/glasgow-haskell-users

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