← Back to team overview

maria-discuss team mailing list archive

Re: Segfaulting with signal 6

 

On 03/30/2011 07:58 AM, Michael Widenius wrote:
> 
> Hi!
> 
>>>>>> "Lance" == Lance Albertson <lance@xxxxxxxxxx> writes:
> 
> Lance> I've run into another weird problem where MariaDB is segfaulting
> Lance> and dieing on Gentoo Hardened Linux. I can't figure out if its a weird
> Lance> situation with my Gentoo environment on the machine or something with
> Lance> MariaDB itself. I don't have this problem on the other machine running
> Lance> MariaDB. It seems to happen under load about once or twice a day. I have
> Lance> a nearly identical machine that doesn't have any of these problems.
> 
> Lance> I'm running mariadb-5.1.50 under Hardened Gentoo. The compiled flags are:
> 
> Lance> ---
> Lance> Configuration summary for MariaDB Server version 5.1.50-MariaDB
> 
> <cut>
> 
> Lance> mysqld: malloc.c:5153: malloc_consolidate: Assertion
> Lance> `nextchunk->fd_nextsize->bk_nextsize == nextchunk' failed.
> Lance> 110329 13:11:25 [ERROR] mysqld got signal 6 ;
> 
> This looks like memory overrun, something that we have not seen in
> MariaDB for a long time. (We are testing all builds with valgrind to
> ensure we don't have any memory overruns).
> 
> <cut>
> 
> Is there a way we could install a debug binary on the machine in
> question so that we could be able to debug this?
> 
> (We would need a binary compiled with debug + a core to be able to
> find out what's going on).
> 
> The easyest way to get a debug binary is to get the source and
> compile it with:
> 
> ./BUILD/compile-pentium-debug-max
> 
> and then just copy it over your original mysqld binary.

I will try and get it compiled with debug symbols under Gentoo using
their documentation. If that doesn't work I'll do it manually.

> If you can get us access to the system, we can help you with this.

If we get to the point where I can't get it farther with it, I'll do
that but for now I feel more comfortable doing it myself.

> You can find us at '#maria' channel on freenode if you want to discuss
> this real time.

Thanks for that tip!

So far the machine has been running smoothly. I just did a minor glibc
upgrade to see if that helped it or not. I have monit monitoring mysqld
so that it will kick it more automatically.

Cheers-

-- 
Lance Albertson
Systems Administrator / Architect                        Open Source Lab
Network Services                                 Oregon State University

Attachment: signature.asc
Description: OpenPGP digital signature


References