[rt-users] Testing 4.0.0rc5 - experiences upgrading from 3.6.4 on RHEL6

[Darren Nickerson]

On Feb 24, 2011, at 12:08 PM, Darren Nickerson wrote:
> 
>> In your case, does the page eventually came out rendered at all,
>> like after 5min?
> 
> I will try to let it wait longer ... I think I have waited as long as 10 minutes in the past, but it's worth trying and reporting back to you.

So, we had two instances of the hang today, and they each followed a similar pattern.

In at least one case the problem cleared itself after some time. I do not know how long, it was a background apache thread started by rt-mailgate that eventually cleared, it was not a browser session.

Of the http worker threads, each one is blocked in a semop call:

[root at rt4 Plack-0.9970]# strace -p 30307
Process 30307 attached - interrupt to quit
semop(1802244, {{0, -1, SEM_UNDO}}, 1^C <unfinished ...>
Process 30307 detached
[root at rt4 Plack-0.9970]# strace -p 30308
Process 30308 attached - interrupt to quit
semop(1802244, {{0, -1, SEM_UNDO}}, 1^C <unfinished ...>
Process 30308 detached
[root at rt4 Plack-0.9970]# strace -p 30309
Process 30309 attached - interrupt to quit
semop(1802244, {{0, -1, SEM_UNDO}}, 1^C <unfinished ...>
Process 30309 detached

except for one which is reading from fd 1:

[root at rt4 Plack-0.9970]# strace -p 30310
Process 30310 attached - interrupt to quit
read(1, ^C <unfinished ...>

That FD is a network connection to our database server:

[root at rt4 Plack-0.9970]# ls -l /proc/30310/fd/1
lrwx------. 1 root root 64 Feb 24 17:44 /proc/30310/fd/1 -> socket:[281592]
[root at rt4 Plack-0.9970]# netstat -antep | grep 281592
tcp        0      5 10.0.12.149:49410           10.0.11.100:3306            ESTABLISHED 48         281592     30310/httpd     

The database server has no record of that tcp connection any longer, and mysqladmin processlist shows all threads sleeping.



>> and can you see if it makes any difference if you change around line
>> 222 of RT::Interface::Web::Handler from:
>> 
>>  my $h = RT::Interface::Web::Handler::NewHandler(
>>    'HTML::Mason::PSGIHandler::Streamy');
>> to: 
>> 
>>  my $h = RT::Interface::Web::Handler::NewHandler(
>>    'HTML::Mason::PSGIHandler');

I have not yet tried this. Given the new detailed information above, does it still make sense to do so?

-Darren