Help on perl core dump

karthik sankaran

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Jan 28, 2013, 6:48:08 AM1/28/13

to begi...@perl.org

gdb /usr/bin/perl /piroot/corefiles/core.21394

GNU gdb (GDB) Red Hat Enterprise Linux (7.2-56.el6)

Copyright (C) 2010 Free Software Foundation, Inc.

License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html
>

This is free software: you are free to change and redistribute it.

There is NO WARRANTY, to the extent permitted by law. Type "show copying"

and "show warranty" for details.

This GDB was configured as "x86_64-redhat-linux-gnu".

For bug reporting instructions, please see:

<http://www.gnu.org/software/gdb/bugs/>...

Reading symbols from /usr/bin/perl...(no debugging symbols found)...done.

[New Thread 21394]

warning: .dynamic section for "/lib64/libc.so.6" is not at the expected
address (wrong library or version mismatch?)

Reading symbols from /usr/lib64/perl5/CORE/libperl.so...(no debugging
symbols found)...done.

Loaded symbols for /usr/lib64/perl5/CORE/libperl.so

Reading symbols from /lib64/libresolv.so.2...(no debugging symbols
found)...done.

Loaded symbols for /lib64/libresolv.so.2

Reading symbols from /lib64/libnsl.so.1...(no debugging symbols
found)...done.

Loaded symbols for /lib64/libnsl.so.1

Reading symbols from /lib64/libdl.so.2...(no debugging symbols
found)...done.

Loaded symbols for /lib64/libdl.so.2

Reading symbols from /lib64/libm.so.6...(no debugging symbols found)...done.

Loaded symbols for /lib64/libm.so.6

Reading symbols from /lib64/libcrypt.so.1...(no debugging symbols
found)...done.

Loaded symbols for /lib64/libcrypt.so.1

Reading symbols from /lib64/libutil.so.1...(no debugging symbols
found)...done.

Loaded symbols for /lib64/libutil.so.1

Reading symbols from /lib64/libpthread.so.0...(no debugging symbols
found)...done.

[Thread debugging using libthread_db enabled]

Loaded symbols for /lib64/libpthread.so.0

Reading symbols from /lib64/libc.so.6...(no debugging symbols found)...done.

Loaded symbols for /lib64/libc.so.6

Reading symbols from /lib64/ld-linux-x86-64.so.2...(no debugging symbols
found)...done.

Loaded symbols for /lib64/ld-linux-x86-64.so.2

Reading symbols from /usr/lib64/libfreebl3.so...(no debugging symbols
found)...done.

Loaded symbols for /usr/lib64/libfreebl3.so

Reading symbols from /usr/local/lib64/perl5/auto/DBI/DBI.so...done.

Loaded symbols for /usr/local/lib64/perl5/auto/DBI/DBI.so

Reading symbols from /usr/lib64/perl5/auto/List/Util/Util.so...(no
debugging symbols found)...done.

Loaded symbols for /usr/lib64/perl5/auto/List/Util/Util.so

Reading symbols from /usr/local/lib64/perl5/auto/Time/HiRes/HiRes.so...done.

Loaded symbols for /usr/local/lib64/perl5/auto/Time/HiRes/HiRes.so

Reading symbols from /lib64/librt.so.1...(no debugging symbols
found)...done.

Loaded symbols for /lib64/librt.so.1

Reading symbols from /usr/lib64/perl5/auto/Sys/Hostname/Hostname.so...(no
debugging symbols found)...done.

Loaded symbols for /usr/lib64/perl5/auto/Sys/Hostname/Hostname.so

Reading symbols from /usr/local/lib64/perl5/auto/Params/Util/Util.so...done.

Loaded symbols for /usr/local/lib64/perl5/auto/Params/Util/Util.so

Reading symbols from
/usr/local/lib64/perl5/auto/Package/Stash/XS/XS.so...done.

Loaded symbols for /usr/local/lib64/perl5/auto/Package/Stash/XS/XS.so

Reading symbols from
/usr/local/lib64/perl5/auto/List/MoreUtils/MoreUtils.so...done.

Loaded symbols for /usr/local/lib64/perl5/auto/List/MoreUtils/MoreUtils.so

Reading symbols from
/usr/local/lib64/perl5/auto/Params/Validate/XS/XS.so...done.

Loaded symbols for /usr/local/lib64/perl5/auto/Params/Validate/XS/XS.so

Reading symbols from /usr/lib64/perl5/auto/IO/IO.so...(no debugging symbols
found)...done.

Loaded symbols for /usr/lib64/perl5/auto/IO/IO.so

Reading symbols from /usr/lib64/perl5/auto/Fcntl/Fcntl.so...(no debugging
symbols found)...done.

Loaded symbols for /usr/lib64/perl5/auto/Fcntl/Fcntl.so

Reading symbols from /usr/lib64/perl5/auto/Storable/Storable.so...(no
debugging symbols found)...done.

Loaded symbols for /usr/lib64/perl5/auto/Storable/Storable.so

Reading symbols from /usr/lib64/perl5/auto/Encode/Encode.so...(no debugging
symbols found)...done.

Loaded symbols for /usr/lib64/perl5/auto/Encode/Encode.so

Reading symbols from /usr/local/lib64/perl5/auto/YAML/Syck/Syck.so...done.

Loaded symbols for /usr/local/lib64/perl5/auto/YAML/Syck/Syck.so

Reading symbols from /usr/lib64/perl5/auto/XML/Parser/Expat/Expat.so...(no
debugging symbols found)...done.

Loaded symbols for /usr/lib64/perl5/auto/XML/Parser/Expat/Expat.so

Reading symbols from /lib64/libexpat.so.1...(no debugging symbols
found)...done.

Loaded symbols for /lib64/libexpat.so.1

Reading symbols from /usr/lib64/perl5/auto/Socket/Socket.so...(no debugging
symbols found)...done.

Loaded symbols for /usr/lib64/perl5/auto/Socket/Socket.so

Reading symbols from /usr/local/lib64/perl5/auto/DBD/mysql/mysql.so...done.

Loaded symbols for /usr/local/lib64/perl5/auto/DBD/mysql/mysql.so

Reading symbols from /usr/local/mysql/lib/libmysqlclient.so.18...done.

Loaded symbols for /usr/local/mysql/lib/libmysqlclient.so.18

Reading symbols from /lib64/libz.so.1...(no debugging symbols found)...done.

Loaded symbols for /lib64/libz.so.1

Reading symbols from /lib64/libgcc_s.so.1...(no debugging symbols
found)...done.

Loaded symbols for /lib64/libgcc_s.so.1

Reading symbols from /lib64/libnss_files.so.2...(no debugging symbols
found)...done.

Loaded symbols for /lib64/libnss_files.so.2

Core was generated by `/usr/bin/perl ./computeMos.pl'.

Program terminated with signal 11, Segmentation fault.

#0 0x00007f320ea364a3 in ptmalloc_unlock_all2 () from /lib64/libc.so.6

Missing separate debuginfos, use: debuginfo-install
perl-5.10.1-119.el6_1.1.x86_64

(gdb)

(gdb) where

#0 0x00007f320ea364a3 in ptmalloc_unlock_all2 () from /lib64/libc.so.6

#1 0x0000000000722010 in ?? ()

#2 0x00007f320fd3a500 in Perl_leave_scope () from
/usr/lib64/perl5/CORE/libperl.so

#3 0x0000000000000000 in ?? ()

--
Regards,
karthik

Mike Dunaway

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Jan 28, 2013, 10:44:10 AM1/28/13

to karthik sankaran, begi...@perl.org

So what was the question?

Bob goolsby

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Jan 28, 2013, 10:19:09 PM1/28/13

to Perl Beginners, karthik sankaran

I suspect the real question is: "Why am I trying to debug a Perl
configuration problem with the gdb()? Why didn't I read the first few
lines of the error message (starting with "warning:") and fix the
problem?" I get enough gdb() practice running against some gnarly
(and barkley) C code in my current contract. ("We have this piece of
Legacy that we lost the source on, and we'd like it rewritten in a
more modern/friendly language....")

Just because you can, does not mean you should break out the run-time
debugger for every possible problem you encounter. As someone on Perl
Monks says (Toolic?) "When your only tool is a hammer, every problem
looks like your thumb."

B

> --
> To unsubscribe, e-mail: beginners-...@perl.org
> For additional commands, e-mail: beginne...@perl.org
> http://learn.perl.org/
>
>

--

Bob Goolsby
bob.g...@gmail.com

karthik sankaran

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Jan 29, 2013, 12:27:37 AM1/29/13

to Bob goolsby, Perl Beginners

"Why am I trying to debug a Perl
configuration problem with the gdb()? Why didn't I read the first few
lines of the error message (starting with "warning:") and fix the
problem?"

I am seeing a lot of core dump files created by perl. The only way I know
to go through the core dump files is through the gdb. Only after going
through the gdb am seeing the WARNING message. rt?

And the last few lines of the gbd shows that perl is core dumping becaue of
some libc issues. I was trying to find if I can get some help to fix this
problem

(gdb) where

#0 0x00007f320ea364a3 in ptmalloc_unlock_all2 () from /lib64/libc.so.6

#1 0x0000000000722010 in ?? ()

#2 0x00007f320fd3a500 in Perl_leave_scope () from
/usr/lib64/perl5/CORE/libperl.so

#3 0x0000000000000000 in ?? ()

--
Regards,
karthik

John SJ Anderson

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Jan 29, 2013, 12:33:06 AM1/29/13

to Perl Beginners

On Mon, Jan 28, 2013 at 9:27 PM, karthik sankaran
<skarthi...@gmail.com> wrote:
> I am seeing a lot of core dump files created by perl.

The perl-beginners list isn't the most appropriate forum for this
issue -- dealing with the interpreter core dumping and how to
troubleshoot that particular situation is well out of "beginner"
territory -- but if you can give us a bit more information, we may be
able to suggest better places for you to ask these questions.

Along those lines, some questions:

* Is there a specific program or piece of code that's causing the core
dump? (I.e., what are you doing to make Perl dump core? -- what's the
minimum amount of code needed to produce this segfault?)

* Can you reproduce this core dump on another machine? (I.e., have you
ruled out that there's some hardware issue at the bottom of this)

* It looks as if this is the Perl 5.10 that ships with RHEL6 (or maybe
CentOS?) -- could you confirm that? If you build your own copy of
Perl, does the segfault still happen?

thanks,
john.

karthik sankaran

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Jan 30, 2013, 12:12:29 AM1/30/13

to John SJ Anderson, Perl Beginners

thanks for the reply,

The perl code uses multi-processing functionality. A parent child
functionality where the parent invokes as many childs needed and will
terminate once the child completes its process.

Yes I am seeing this core dumps in other servers also. I info I forgot to
mention is I am using perl 5.10.1, I suspected that whether this could be
an issue and I have upgraded by perl version to 5.16.2,

Will run my code on this version and will update you on the status,

karthik sankaran

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Jan 30, 2013, 6:14:15 AM1/30/13

to John SJ Anderson, Perl Beginners

Hi --

Even after upgrading to the latest version of perl I am seeing the core
dump files created.

--
Regards,
karthik

Jim Gibson

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Jan 30, 2013, 10:37:36 AM1/30/13

to Perl Beginners

On Jan 30, 2013, at 3:14 AM, karthik sankaran wrote:

> Hi --
>
> Even after upgrading to the latest version of perl I am seeing the core
> dump files created.
>

I would make sure that perl and all of the XS modules you are using were compiled with the same compiler and libraries. When you upgraded, did you compile perl from source or install a binary distribution? Did you reinstall all of the modules?

karthik sankaran

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Jan 31, 2013, 12:17:14 AM1/31/13

to Jim Gibson, Perl Beginners

I compiled it from the source and Yes , in installed all the necessary
modules again.

this is the latest info from the gdb after upgrading to the perl version
16, subversion 2 (v5.16.2) built for x86_64-linux

Program terminated with signal 11, Segmentation fault.

#0 0x00007f0686355c47 in net_real_write (net=0x29a7980, packet=0x29b6400
"\005", len=9) at
/pb2/build/sb_0-5715375-1337072270.49/mysql-5.5.25/sql/net_serv.cc:577
577 /pb2/build/sb_0-5715375-1337072270.49/mysql-5.5.25/sql/net_serv.cc:
No such file or directory.
in
/pb2/build/sb_0-5715375-1337072270.49/mysql-5.5.25/sql/net_serv.cc

Missing separate debuginfos, use: debuginfo-install

glibc-2.12-1.80.el6_3.6.x86_64 libgcc-4.4.6-3.el6.x86_64
nss-softokn-freebl-3.12.9-11.el6.x86_64 zlib-1.2.3-27.el6.x86_64
(gdb) where
#0 0x00007f0686355c47 in net_real_write (net=0x29a7980, packet=0x29b6400
"\005", len=9) at
/pb2/build/sb_0-5715375-1337072270.49/mysql-5.5.25/sql/net_serv.cc:577
#1 0x00007f06863561b3 in net_flush (net=0x29ae560) at
/pb2/build/sb_0-5715375-1337072270.49/mysql-5.5.25/sql/net_serv.cc:338
#2 0x00007f0686356347 in net_write_command (net=0x29a7980, command=<value
optimized out>, header=0x0, head_len=0, packet=0x7fff4c914b70 "'", len=4)
at
/pb2/build/sb_0-5715375-1337072270.49/mysql-5.5.25/sql/net_serv.cc:478
#3 0x00007f068635350d in cli_advanced_command (mysql=0x29a7980,
command=<value optimized out>, header=0x0, header_length=0,
arg=0x7fff4c914b70 "'", arg_length=4,
skip_check=1 '\001', stmt=0x29b5e60) at
/pb2/build/sb_0-5715375-1337072270.49/mysql-5.5.25/sql-common/client.c:841
#4 0x00007f068634a5bd in mysql_stmt_close (stmt=0x29b5e60) at
/pb2/build/sb_0-5715375-1337072270.49/mysql-5.5.25/libmysql/libmysql.c:4670
#5 0x00007f0686780025 in mysql_st_destroy (sth=<value optimized out>,
imp_sth=0x29b5bd0) at dbdimp.c:4150
#6 0x00007f068678933a in XS_DBD__mysql__st_DESTROY (cv=<value optimized
out>) at ./mysql.xsi:774
#7 0x00007f0688c5ecb4 in XS_DBI_dispatch () from
/usr/local/lib/perl5/site_perl/5.16.2/x86_64-linux/auto/DBI/DBI.so
#8 0x0000000000497ad8 in Perl_pp_entersub ()
#9 0x0000000000434066 in Perl_call_sv ()
#10 0x00000000004a7e2c in S_curse ()
#11 0x00000000004a860d in Perl_sv_clear ()
#12 0x00000000004a8bd6 in Perl_sv_free2 ()
#13 0x000000000049eb5b in S_visit ()
#14 0x00000000004a907e in Perl_sv_clean_objs ()
#15 0x00000000004380f5 in perl_destruct ()
#16 0x000000000041e0ac in main ()
(gdb)

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> To unsubscribe, e-mail: beginners-...@perl.org
> For additional commands, e-mail: beginne...@perl.org
> http://learn.perl.org/
>
>
>

--

Regards,
karthik

John SJ Anderson

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Jan 31, 2013, 12:24:58 AM1/31/13

to Perl Beginners

On Wed, Jan 30, 2013 at 9:17 PM, karthik sankaran
<skarthi...@gmail.com> wrote:
> I compiled it from the source and Yes , in installed all the necessary
> modules again.
>
> this is the latest info from the gdb after upgrading to the perl version
> 16, subversion 2 (v5.16.2) built for x86_64-linux
>
> Program terminated with signal 11, Segmentation fault.
> #0 0x00007f0686355c47 in net_real_write (net=0x29a7980, packet=0x29b6400
> "\005", len=9) at
> /pb2/build/sb_0-5715375-1337072270.49/mysql-5.5.25/sql/net_serv.cc:577
> 577 /pb2/build/sb_0-5715375-1337072270.49/mysql-5.5.25/sql/net_serv.cc:

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

That's not coming from Perl. I think you have a problem with your
MySQL installation.

j.

karthik sankaran

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Feb 11, 2013, 4:23:01 AM2/11/13

to John SJ Anderson, Perl Beginners

Hi Guys,

Here is something I got from latest core dump files,

[root@DS002009 mos]# perl -v

This is perl 5, version 16, subversion 2 (v5.16.2) built for x86_64-linux

Copyright 1987-2012, Larry Wall

Perl may be copied only under the terms of either the Artistic License or
the
GNU General Public License, which may be found in the Perl 5 source kit.

Complete documentation for Perl, including FAQ lists, should be found on
this system using "man perl" or "perldoc perl". If you have access to the
Internet, point your browser at http://www.perl.org/, the Perl Home Page.

[root@DS002009 mos]# gdb /usr/bin/perl core.17537

GNU gdb (GDB) Red Hat Enterprise Linux (7.2-56.el6)
Copyright (C) 2010 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html
>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law. Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-redhat-linux-gnu".
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>...
Reading symbols from /usr/bin/perl...(no debugging symbols found)...done.

[New Thread 17537]

warning: .dynamic section for "/usr/local/mysql/lib/libmysqlclient.so.18"

is not at the expected address (wrong library or version mismatch?)

Reading symbols from /lib64/libnsl.so.1...(no debugging symbols
found)...done.
Loaded symbols for /lib64/libnsl.so.1
Reading symbols from /lib64/libdl.so.2...(no debugging symbols
found)...done.
Loaded symbols for /lib64/libdl.so.2
Reading symbols from /lib64/libm.so.6...(no debugging symbols found)...done.
Loaded symbols for /lib64/libm.so.6
Reading symbols from /lib64/libcrypt.so.1...(no debugging symbols
found)...done.
Loaded symbols for /lib64/libcrypt.so.1
Reading symbols from /lib64/libutil.so.1...(no debugging symbols
found)...done.
Loaded symbols for /lib64/libutil.so.1

Reading symbols from /lib64/libc.so.6...(no debugging symbols found)...done.
Loaded symbols for /lib64/libc.so.6
Reading symbols from /lib64/ld-linux-x86-64.so.2...(no debugging symbols
found)...done.
Loaded symbols for /lib64/ld-linux-x86-64.so.2

Reading symbols from /lib64/libfreebl3.so...(no debugging symbols
found)...done.
Loaded symbols for /lib64/libfreebl3.so
Reading symbols from
/usr/local/lib/perl5/site_perl/5.16.2/x86_64-linux/auto/DBI/DBI.so...(no