Misc #8962
closed[DOC] add step to enable Generational GC merits in README.EXT*
Description
=begin
Is there any chance to reap the benefit of new Generational GC merits for
C-extension library authors?
== Background
First of all: RGenGC is great. Ko1 showed that it could make significant
performance improvement at RubyKaigi2013. (especially P82)
((<RubyKaigi2013-ko1.pdf|URL:http://www.atdot.net/~ko1/activities/RubyKaigi2013-ko1.pdf>))
I guess the improvement is triggered by marking most (or all?) of built-in
classes as WB-protected struct to work with Generational GC.
== Motivation
As an extension library author, I want to try to get the performance merit.
But there is no document or guide to enable it.
The PDF says "Inserting WBs step by step, and increase performance gradually",
and I believe it is the greatest point of RGenGC, but there is no guide to
proceed with the steps for now. It's sad.
== Subject
Could you write about it as a document, ko1 or anyone?
I guess it's good to be written at ((%README.EXT*%)).
(The case of ((%iseq.c%)) may be used as an example.)
I'm glad to see the documents are written before Ruby 2.1 release.
== Restriction
Sorry for the absence of my knowledge. Because I'm not good at
RGenGC, I could't write the document by myself but could only request.
PS
I guess this issue depends on #3064 (sorry, in Japanse), the request of
documenting (({RTypedData})), because there is no interface to specify
(({FL_WB_PROTECTED})) flag with traditional (({RData})).
=end