8.1-RELEASE: [zfs] [kmem] zfs destroy snapshot results in panic: kmem_map too small

[Jeremy Chadwick]

On Fri, Sep 24, 2010 at 03:46:49PM +0300, Andriy Gapon wrote:
> on 24/09/2010 15:33 Jeremy Chadwick said the following:
> > On Fri, Sep 24, 2010 at 01:24:46PM +0200, Leroy van Logchem wrote:
> >> -----------------------------------------------------------------------------
> >> Problem          : Kernel panic "kmem_malloc(114688): kmem_map too small
> >> Trigger          : Destroy ZFS snapshots (each bigger >80GB)
> >> Version          : FreeBSD 8.1-RELEASE (GENERIC AMD64 but with DDB)
> >> ...
> >> panic: kmem_malloc(114688): kmem_map too small: 3307884544 total allocated
> >> cpuid = 2
> >> KDB: stack backtrace:
> >> db_trace_self_wrapper() at db_trace_self_wrapper+0x2a
> >> panic() at panic+0x182
> >> kmem_malloc() at kmem_malloc+0x5b5
> >> uma_large_malloc() at uma_large_malloc+0x4a
> >> malloc() at malloc+0x14b
> >> zio_compress_data() at zio_compress_data+0xa2
> >> zio_write_bp_init() at zio_write_bp_init+0xc2
> >> zio_exectute() at zio_execute+0x77
> >> taskq_run_safe() at taskq_run_safe+0x13
> >> taskqueue_run() at taskqueue_run+0x91
> >> taskqueue_thread_loop() at taskqueue_thread_loop+0x3f
> >> fork_exit() at fork_exit+0x12a
> >> fork_trampoline() at fork_trampoline+0xe
> >> --- trap 0, rip = 0, rsp = 0xffffff81261edd30, rbp = 0 ---
> >> panic: kmem_malloc(118784): kmem_map too small: 3307884544 total allocated
> >> cpuid = 2
> > 
> > Can you please provide uname -a output?  The built date of your kernel
> > matters in this case.  The panic looks like uma(9) is in use
> 
> No, it doesn't.

You're right, sorry, I missed the malloc(9) call.  (I thought it was
zio_compress_data() followed by uma_large_malloc()).

Leroy, you can ignore my advice of adjusting your loader.conf with the
tunable in question.

-- 
| Jeremy Chadwick                                   jdc at parodius.com |
| Parodius Networking                       http://www.parodius.com/ |
| UNIX Systems Administrator                  Mountain View, CA, USA |
| Making life hard for others since 1977.              PGP: 4BD6C0CB |