>> > Hello, I've been plagued by apache2 segfaults ever since I started
>> > using Interchange::Link years ago. The latest Link.pm has ALERT
>> > messages accompanying the segfaults in error_log:
>> >
>> > ALERT: bad pipe signal received for /page.html
>> > [Sat Dec 09 10:27:55 2006] [notice] child pid 21337 exit signal
>> > Segmentation fault (11)
>> >
>> > Does anyone have any advice on solving this? I'm using
>> apache-2.0.58
>> > and mod_perl-2.0.2 in Gentoo Linux.
>>
>> Also, here is the portion of Link.pm that the ALERT seems to come
>> from:
>>
>> # Return this message to the browser when the server is not running.
>> # Log an error log entry if set to notify
>>
>> sub die_page {
>>
>> my $r = shift;
>> my $msg;
>>
>> warn "ALERT: bad pipe signal received for $ENV{SCRIPT_NAME}\n";
>>
>> $r->content_type ("text/html");
>> $r->print (<<EOF);
>> <HTML><HEAD><TITLE>Interrupted</TITLE></HEAD>
>> <BODY BGCOLOR="#FFFFFF">
>> <H3>Someone pressed stop...</H3>
>> <P>
>> We have aborted this request because someone terminated it.
>> Please try again soon.
>> </BODY></HTML>
>> EOF
>>
>> }
>>
>> Please let me know if you have any ideas.
>
> The segfaults are eliminated by commenting out the $r stuff in the
> die_page sub. I still get the ALERTs though. Does anyone have any
> advice on figuring out why I'm having the bad pipe problem? Is there
> an easy way to add extra debugging info to the sub?
>
> Also, restarting IC with PERL_SIGNALS=unsafe increases the ALERTs
> 50 fold.
I've been seeing this too, on my Apache 2 and latest Link.pm. I also
had to use PERL_SIGNALS=unsafe and so I get quite a lot of these.
The visible effect on the browser is that the page or image (which
Link.pm apparently still has some part in delivering) does not load.
I get them myself when browsing and testing my websites, and I have
never stopped loading a page or had any other problems on non-IC
sites I host.
I was told the problem stems from either the browser and a stop
button or some other network fault. I may go back to Apache 1.3 to
get around this.
I've been working on this all day and I think I may have a solution.
Incidentally, I want to mention that if I add $! to the Link.pm warn
line, I can see that there are two different types of ALERTs in
error_log:
Broken pipe
Inappropriate ioctl for device
Also incidentally, hitting F5 repeatedly always prints a few ALERTS in
error_log, but the number of ALERTs printed seems to be about 10 times
more for an http page than for the same page accessed via https. I
checked and tested the settings in my *:80 and *:443 vhosts trying to
narrow that down, but I didn't come up with anything.
Now, as I mentioned a few posts back, commenting out the html delivery
stuff in the die_page sub of Link.pm eliminates the segfaults in
error_log but not the ALERTs. Today I enabled the prefork mpm in
apache2 and tinkered with the Server/Child settings in interchange.cfg
and httpd.conf and that did seem to reduce the ALERTs somewhat.
After all of this, I've been browsing around my site and I haven't
seen a single image or page fail to load like it used to. The thing
is, ALERTs still show up in error_log even for requests I'm sure I
created myself AND WERE SERVED SUCCESSFULLY. I hypothesize that the
failed requests were because a $SIG{PIPE} was generated for whatever
reason (although not because the user clicked the stop button), the
html was delivered, it caused a segfault, and the request failed. I
should mention though, that if the failing request syndrome is fixed,
it could also be from the apache2, httpd.conf, or interchange.cfg
modifications mentioned above. I doubt it though.
Incidentally, I'd like to mention that the ALERTs can be generated
pretty reliably by hitting the browser's stop button in the middle of
a request, clicking on the same link again or a different link in the
middle of a request (my Mom probably still double clicks links), or
just refreshing the page in the middle of a request.
If the failed requests do stop at this point, I think the die_page
section of Link.pm is doing more harm than good. Is there anything
wrong with not handling $SIG{PIPE} at all?
- Grant
_______________________________________________
interchange-users mailing list
suppressed
http://www.icdevgroup.org/mailman/listinfo/interchange-users
Mail converted by mhonarc 2.6.15
This archive provided courtesy of JSW4.NET, Internet Hosting Services for Small Business.