From: KOSAKI Motohiro <kosaki.motohiro@...>
Date: 2010-07-10T10:56:54+09:00
Subject: [ruby-core:31172] Re: [Bug #2553] Fix pthreads slowness by 	eliminating unnecessary sigprocmask calls

2010/7/10 KOSAKI Motohiro <kosaki.motohiro@gmail.com>:
> 2010/7/10 Andre Nathan <redmine@ruby-lang.org>:
>> Issue #2553 has been updated by Andre Nathan.
>>
>>
>> Hello
>>
>> I was trying to update the ubuntu ruby 1.8.7 package with this patch, but I'm still seeing the bad performance. The patch has the following line:
>>
>> if test -n "`(/lib/libc.so.6 2>/dev/null | fgrep 'Native POSIX Threads') 2> /dev/null`"; then
>>    use_context=yes
>> fi
>>
>> Isn't the use of setcontext necessary only for linuxthreads, i.e. if the system doesn't have native posix threads? In that case, shouldn't the test be "test -z", so that use_context is set to yes if "Native POSIX Threads" does *not* appear in that output?
>>
>> Apologies if I have misunderstood the patch.
>
> Oops, this patch only works on 32bit machine, because some 64bit
> distro don't have /lib/libc.so.6 (instead they use /lib64), and this
> condition select use_context=yes.
>
> I'll update this soon.
> And, if you are using 32bit distro, please show your /lib/libc.so.6
> execution result.
>
> I'm very sorry this.

following patch works both 32bit and 64bit on my environment.

$ svn diff
Index: configure.in
===================================================================
--- configure.in        (リビジョン 28594)
+++ configure.in        (作業コピー)
@@ -1151,7 +1151,7 @@
 if test x"$rb_with_pthread" = xyes; then
     AS_CASE("$target_cpu:$target_os:$cross_compiling",
     [*:linux*:no], [
-        if test -n "`(/lib/libc.so.6 2>/dev/null | fgrep 'Native
POSIX Threads') 2> /dev/null`"; then
+        if test -n "`(/lib/libc.so.6 2>/dev/null | fgrep
'linuxthreads') 2> /dev/null`"; then
            use_context=yes
        fi
     ],