[ruby-core:38714] Re: Issue of Passenger and ruby-trunk

Hi,

As I described on [ruby-core:37759], please use
"rb_reserved_fd_p(int fd)".  If you have any inconvenience, please teach us.

Thanks,
Koichi


(2011/08/02 20:46), Hongli Lai wrote:
> Hi Koichi. Thanks for informing us about this problem. Does Ruby 1.9.3
> provide some kind of API for obtaining all file descriptors that we
> must not close?
> 
> - Hongli
> 
> 2011/7/2 SASADA Koichi <[e-mail]>:
>> Hi,
>>
>> This is issue about Passenger.  I've also sent it to ruby-core mailing list.
>>
>> I can't find the contacts to developers of Passenger.  So I sent you
>> this e-mail.  Please inform them about it.
>>
>> Regards,
>> Koichi
>>
>> -------- Original Message --------
>> Subject: [ruby-core:37727] Issue of Passenger and ruby-trunk
>> Date: Sat, 2 Jul 2011 10:17:57 +0900
>> From: SASADA Koichi <[e-mail]>
>> Reply-To: [e-mail]
>> To: [e-mail]
>>
>> Hi,
>>
>> We received a bug report ([ruby-dev:44011] [Ruby 1.9 - Bug #4958], in
>> Japanese) that says Passenger (*1) doesn't work with current trunk.  I
>> surveyed it and found out the reason.
>>
>> *1: http://www.modrails.com/
>>
>> In short, Passenger close most of file descriptors (fd) by
>> NativeSupport.close_all_file_descriptors().  However, current Ruby uses
>> 2 fds for to communicate between [signal handler] <-> [timer thread] <->
>> [ruby thread].  I can run Passenger on commented out
>> "NativeSupport.close_all_file_descriptors" line.
>>
>>
>> Details:
>>
>> (1) Ruby-side:
>>
>> To avoid timer thread frequent invocation, we modified them totally.
>> And we decided to use pipe to communicate between [signal handler] <->
>> [timer thread] <-> [ruby thread].  We named this pipe "communication
>> pipe".  Ruby opens pipe at first.  Ruby also open pipe after fork().
>>
>> (2) Passenger-side:
>>
>> I assume that Passenger fork ruby process if request reached.  At first,
>> forked process close all file descriptors to avoid file descriptor leak.
>>  The method NativeSupport.close_all_file_descriptors(left_fds) forcibly
>> closes all file descriptors except left_fds.
>>
>> quoted from passenger-3.0.5/lib/phusion_passenger/abstract_server.rb:
>>> # During Passenger's early days, we used to close file descriptors based
>>> # on a white list of file descriptors. That proved to be way too fragile:
>>> # too many file descriptors are being left open even though they shouldn't
>>> # be. So now we close file descriptors based on a black list.
>>> #
>>> # Note that STDIN, STDOUT and STDERR may be temporarily set to
>>> # different file descriptors than 0, 1 and 2, e.g. in unit tests.
>>> # We don't want to close these either.
>>> file_descriptors_to_leave_open = [0, 1, 2,
>>>       b.fileno, server_socket.fileno,
>>>       fileno_of(STDIN), fileno_of(STDOUT), fileno_of(STDERR)
>>> ].compact.uniq
>>> NativeSupport.close_all_file_descriptors(file_descriptors_to_leave_open)
>>
>> (3) Problem
>>
>> NativeSupport.close_all_file_descriptors(file_descriptors_to_leave_open)
>> closes communication pipe.  It causes critical problem to run ruby.
>>
>> For exmaple, in report [ruby-dev:44011] [Ruby 1.9 - Bug #4958], the
>> following [BUG] was reported.
>>
>>> /var/log/httpd/error_log:
>>> -------
>>> [ASYNC BUG] thread_timer: select
>>> EBADF
>>>
>>> ruby 1.9.3dev (2011-07-01 trunk 32348) [x86_64-linux]
>>>
>>> [NOTE]
>>> You may have encountered a bug in the Ruby interpreter or extension libraries.
>>> Bug reports are welcome.
>>> For details: http://www.ruby-lang.org/bugreport.html
>>> -----
>>
>> I confirmed that I commented out the line
>> NativeSupport.close_all_file_descriptors, then Passenger run normally.
>>
>>
>> (4) Solution
>>
>> How to solve it?  May I provide some C API or Ruby API to get pipe fds?
>>
>> --
>> // SASADA Koichi at atdot dot net
>>
>>
> 
> 
> 


-- 
// SASADA Koichi at atdot dot net