Add suggestion to profile to find a better set of hot ops for pp_hot.

p4raw-id: //depot/perl@25436

1 files changed, 13 insertions, 0 deletions

diff --git a/pod/perltodo.pod b/pod/perltodo.pod
index 771740e91a..e315cd3023 100644
--- a/pod/perltodo.pod
+++ b/pod/perltodo.pod
@@ -261,6 +261,19 @@ official release".
 There are lots of functions which are retained for binary compatibility.
 Clean these up. Move them to mathom.c, and don't compile for blead?
 
+=head2 am I hot or not?
+
+The idea of F<pp_hot.c> is that it contains the I<hot> ops, the ops that are
+most commonly used. The idea is that by grouping them, their object code will
+be adjacent in the executable, so they have a greater chance of already being
+in the CPU cache (or swapped in) due to being near another op already in use.
+
+Except that it's not clear if these really are the most commonly used ops. So
+anyone feeling like exercising their skill with coverage and profiling tools
+might want to determine what ops I<really> are the most commonly used. And in
+turn suggest evictions and promotions to achieve a better F<pp_hot.c>.
+
+