From: Tanaka Akira <akr@...>
Date: 2010-11-01T21:18:19+09:00
Subject: [ruby-core:32991] Re: [Ruby 1.9-Feature#3905][Open] rb_clear_cache_by_class() called often during GC for non-blocking I/O

2010/10/30 Tanaka Akira <akr@fsij.org>:
> 2010/10/5, Eric Wong <redmine@ruby-lang.org>:
>> Feature #3905: rb_clear_cache_by_class() called often during GC for
>> non-blocking I/O
>> http://redmine.ruby-lang.org/issues/show/3905
>
>> This still causes performance problems with frequent EAGAIN compared to
>> 1.9.1
>>
>> While akr fixed extend to no longer clear cache with empty modules in
>> r28813,
>> the GC phase still scans and clears the cache when the extended object is
>> collected.
>
> The following patch fix the problem?

The following patch may be better.

% svn diff --diff-cmd diff -x '-u -p'
Index: vm_method.c
===================================================================
--- vm_method.c	(revision 29630)
+++ vm_method.c	(working copy)
@@ -85,6 +85,9 @@ rb_clear_cache_by_class(VALUE klass)
 {
     struct cache_entry *ent, *end;

+    if (RCLASS_M_TBL(klass)->num_entries == 0)
+        return;
+
     rb_vm_change_state();

     if (!ruby_running)
-- 
Tanaka Akira