Do you actually need fastthread?

[gobigdave]

I had some problems installing Passenger on a couple of systems, and
the issues were all related to fastthread. Even after finally getting
things installed, I still ended up with other issues related to
fastthread that I didn't have before. FYI, these were on fully
functioning environments where I moved from Mongrel to Passenger. Pre-
Passenger, I had no fasthread issues. What happens now is that God.rb
will crash after about a day. Interestingly, it dies with a similar
error that prevented me from installing Passenger.

The error:
/usr/local/bin/ruby: symbol lookup error: /usr/local/lib/ruby/gems/1.8/
gems/fastthread-1.0.4/lib/fastthread.so: undefined symbol:
rb_thread_alive_p

This happens on multiple systems, and only after about a day for
normal execution.

What confuses me is that as far as I can tell fasthread isn't even
necessary anymore as long as you have Ruby > 1.8.5. I have:

ruby 1.8.6 (2007-03-13 patchlevel 0) [x86_64-linux]

Does Passenger (2.1.3) really require it? If so, why? One more thing,
I had 0 issues related to Passenger or Fastthread with 2.1.2. It was
only when I installed 2.1.3 from scratch that I had a problem.

Essentially, if it isn't necessary anymore, I prefer to get rid of
anything that is causing me problems.

[Hongli Lai]

Yes, we use fastthread if the Ruby interpreter's version is < 1.9.
Fastthread actually is required for 1.8.6 because we found a few
threading bugs while developing Phusion Passenger, which were fixed by
loading fastthread.

I see that you're using fastthread 1.0.4. 1.0.4 was recently released
(like a month ago or so) and there's a bug in that version related to
rb_thread_alive_p, as shown in your output. The latest version of
fastthread is 1.0.6; you should upgrade.

--
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Web: http://www.phusion.nl/
E-mail: in...@phusion.nl
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[Hongli Lai]

On Mon, Apr 6, 2009 at 6:54 PM, gobigdave <gobi...@gmail.com> wrote:

> Does Passenger (2.1.3) really require it? If so, why? One more thing,
> I had 0 issues related to Passenger or Fastthread with 2.1.2. It was
> only when I installed 2.1.3 from scratch that I had a problem.

I think that at the time you installed 2.1.2, fastthread was still at
version 1.0.0 (it had been in 1.0.0 for a long time). Then 1.0.4 with
the bug was released, and then you installed Phusion Passenger 2.1.3
before fastthread 1.0.6 was released.

[gobigdave]

This is the most likely scenario. I guess I was just lucky. I ended up
going back to fastthread 1.0.1 to prevent the runtime issue, but it
looks like I can upgrade again to 1.0.6.

On Apr 6, 3:26 pm, Hongli Lai <hon...@phusion.nl> wrote:

> On Mon, Apr 6, 2009 at 6:54 PM, gobigdave <gobigd...@gmail.com> wrote:
> > Does Passenger (2.1.3) really require it? If so, why? One more thing,
> > I had 0 issues related to Passenger or Fastthread with 2.1.2. It was
> > only when I installed 2.1.3 from scratch that I had a problem.
>
> I think that at the time you installed 2.1.2, fastthread was still at
> version 1.0.0 (it had been in 1.0.0 for a long time). Then 1.0.4 with
> the bug was released, and then you installed Phusion Passenger 2.1.3
> before fastthread 1.0.6 was released.
>
> --
> Phusion | The Computer Science Company
>
> Web:http://www.phusion.nl/

> E-mail: i...@phusion.nl

[gobigdave]

Nope, I'm still having the problem with fastthread 1.0.6. It's strange
how god.rb runs for about 24 hours before dying with:

/usr/local/bin/ruby: symbol lookup error: /usr/local/lib/ruby/gems/1.8/

gems/fastthread-1.0.6/lib/fastthread.so: undefined symbol:
rb_thread_alive_p

What is interesting is that it happened within 10 minutes on two
separate environments.

I guess I'm going back to 1.0.1 and seeing what happens. Either way,
fastthread has been causing way too many headaches since my upgrade to
Passenger.

[Hongli Lai]

I've reported this problem to the fastthread author.

[Hongli Lai]

gobigdave, are you sure that your Ruby version is 1.8.6-p0, and not
some kind of prerelease version? The problem that you're experiencing
is caused by your Ruby interpreter not having the function
rb_thread_alive_p, but upon inspecting 1.8.6-p0's source code, this
version should have this version.

[gobigdave]

ruby -v # => ruby 1.8.6 (2007-03-13 patchlevel 0) [x86_64-linux]

I installed ruby on three environments (CentOS 5) as follows:

wget ftp://ftp.ruby-lang.org/pub/ruby/1.8/ruby-1.8.6.tar.gz
tar xzvf ruby-1.8.6.tar.gz
cd ruby-1.8.6
./configure
make
make install

Anything else I can check to be sure?

[Hongli Lai]

On Thu, Apr 9, 2009 at 1:31 AM, gobigdave <gobi...@gmail.com> wrote:
>
> ruby -v # => ruby 1.8.6 (2007-03-13 patchlevel 0) [x86_64-linux]
>
> I installed ruby on three environments (CentOS 5) as follows:
>
> wget ftp://ftp.ruby-lang.org/pub/ruby/1.8/ruby-1.8.6.tar.gz
> tar xzvf ruby-1.8.6.tar.gz
> cd ruby-1.8.6
> ./configure
> make
> make install
>
> Anything else I can check to be sure?

After some investigation, it turns out that in 1.8.6-p0 doesn't
publish rb_thread_alive_p to extensions, i.e. it's a static function.
After digging through the code history, it was revealed that
rb_thread_alive_p was made non-static since 1.8.6-p31.

Fastthread's author has just released version 1.0.7 which fixes this problem.

--
Phusion | The Computer Science Company

Web: http://www.phusion.nl/
E-mail: in...@phusion.nl

[gobigdave]

Thanks! I will try version 1.0.7.

On Apr 9, 4:09 am, Hongli Lai <hon...@phusion.nl> wrote:

> On Thu, Apr 9, 2009 at 1:31 AM, gobigdave <gobigd...@gmail.com> wrote:
>
> > ruby -v # => ruby 1.8.6 (2007-03-13 patchlevel 0) [x86_64-linux]
>
> > I installed ruby on three environments (CentOS 5) as follows:
>

> > wgetftp://ftp.ruby-lang.org/pub/ruby/1.8/ruby-1.8.6.tar.gz

> > tar xzvf ruby-1.8.6.tar.gz
> > cd ruby-1.8.6
> > ./configure
> > make
> > make install
>
> > Anything else I can check to be sure?
>
> After some investigation, it turns out that in 1.8.6-p0 doesn't
> publish rb_thread_alive_p to extensions, i.e. it's a static function.
> After digging through the code history, it was revealed that
> rb_thread_alive_p was made non-static since 1.8.6-p31.
>
> Fastthread's author has just released version 1.0.7 which fixes this problem.
>
> --
> Phusion | The Computer Science Company
>
> Web:http://www.phusion.nl/

> E-mail: i...@phusion.nl