Memcached crashing on FreeBSD

[Jason Coene]

I'm running 5.2-RELEASE, so you want rev 1.84.2.1:
 
http://www.freebsd.org/cgi/cvsweb.cgi/~checkout~/src/lib/libc/stdlib/malloc.
c?rev=1.84.2.1

If you would like to provide the ASSERT, I can try it - also, I'm thinking I
can likely replicate this issue by starting a server with a lower memory
limit (currently 512) and flooding it a bit... if we want to do rapid
testing.

Thanks,

Jason

> -----Original Message-----
> From: Jacob Coby [mailto:jcoby at listingbook.com]
> Sent: Wednesday, April 13, 2005 6:43 PM
> To: Jason Coene
> Cc: 'Anatoly Vorobey'; memcached at lists.danga.com
> Subject: Re: Memcached crashing on FreeBSD
> 
> Jason Coene wrote:
> > Well guys, some bad news - "ax" didn't fix the crash!
> >
> > Code I added to main():
> >
> > #ifdef __FreeBSD__
> >     _malloc_options = "ax";
> > #endif
> >
> > The ifdef block is definitely getting picked up, I tested with a printf
> 
> Maybe an assert() needs to be put in slabs_newslab to double check that
> _malloc_options isn't being reset to the defaults?
> 
> > Backtrace from latest crash:
> >
> > (gdb) bt
> > #0  0x280c5d4f in kill () from /lib/libc.so.5
> > #1  0x280ba7f8 in raise () from /lib/libc.so.5
> > #2  0x28132f02 in abort () from /lib/libc.so.5
> > #3  0x2813167e in tcflow () from /lib/libc.so.5
> > #4  0x28131f1b in tcflow () from /lib/libc.so.5
> 
> I'm very naive with the *BSDs, but #3 and #4 confuse me a little bit.  I
> haven't been able to find a version of malloc() in the FreeBSD CVS that
> calls tcflow().  The version that I'm looking at calls pubrealloc(),
> which never calls tcflow().  It'd be nice if the bt showed the params to
> the libc calls..
> 
> http://www.freebsd.org/cgi/cvsweb.cgi/~checkout~/src/lib/libc/stdlib/mallo
> c.c?rev=1.90&content-type=text/plain
> 
> Which version should I be looking at?
> 
> And just for reference:
> 
> tcflow() suspends transmission or reception of data on the object
> referred to by fd, depending on the value of action:
> 
>         TCOOFF suspends output.
> 
>         TCOON  restarts suspended output.
> 
>         TCIOFF transmits a STOP character, which stops the terminal
> device from transmitting data to the system.
> 
>         TCION  transmits a START character, which starts the terminal
> device transmitting data to the system.
> 
>         The default on open of a terminal file is that neither its input
> nor its output is suspended.
> 
> > #5  0x281322d6 in malloc () from /lib/libc.so.5
> > #6  0x0804b595 in slabs_newslab (id=5) at slabs.c:111
> 
> ln 111 looks like:
> 
> ptr = malloc(len);
> 
> where len is: int len = POWER_BLOCK;
> 
> Not really helpful, I know.  I'm just hoping to spark one of those AHA!
> moments :)
> 
> --
> -Jacob