Repeatable ZFS "kmem map too small" panic on 8.0-STABLE

[Artem Belevich]

What do following sysctls show on your box?

hw.physmem:
vm.kmem_size
vm.kmem_size_max
vfs.zfs.arc_max

--Artem



On Fri, Jan 22, 2010 at 10:09 AM, Doug Poland <doug at polands.org> wrote:
>
> On Fri, January 22, 2010 07:22, Doug Poland wrote:
>> On Fri, January 22, 2010 00:09, Artem Belevich wrote:
>>> On Thu, Jan 21, 2010 at 8:28 PM, Doug Poland <doug at polands.org>
>>> wrote:
>>>> Interesting discussion :)  I added vm.kmem_size="20G" to
>>>> /boot/loader.conf per your instructions.  This time, it didn't
>>>> panic at the same point in the test, however, it appears the
>>>> filesystem is "hanging".
>>>>
>>>> On the fdisk test, I hit <CTRL> T and get:
>>>> cmd: fsdisk 37066 [zio->io_cv)] 245.62r 0.12u 25.10s 0
>>>>
>>>> My various metrics are still running, but anything that needs the
>>>> filesystem appears "stuck".
>>>>
>>>> The memory usage of the item "solaris" (vmstat -m | grep solaris)
>>>> spiked at 3334781952 (3180.30 MiB).
>>>>
>>>> # zpool iostat 2, a <CTRL> T shows:
>>>> load: 0.00  cmd: zpool 934 [tx->tx_quiesce_done_cv)] 2052.45r 0.06
>> u 0.39s 0% 0k
>>>>
>>>> # vmstat -v | grep solaris to disk every second and it's hung at:
>>>> load: 0.00  cmd: sh 38551 [zfs] 909.85r 0.00u 0.00s 0% 16k
>>>>
>>>> Any suggestions!
>>>>
>>> Next step would be to set vfs.zfs.arc_max to a value that's somewhat
>>> below your physical memory size. Let's say - 1G or so. On my box
>>> with
>>> 8GB of RAM I set these values:
>>>
>>> vfs.zfs.arc_max="6500M"
>>> vfs.zfs.arc_min="4G"
>>>
>> OK, I'll give that a shot...
>>
>
> panic: kmem_malloc(131072): kmem_map too small: 3593236480 total
> allocate d
>
> # cat /boot/loader.conf
> vfs.root.mountfrom="zfs:bethesda"
> vfs.zfs.arc_max="1G"
> vm.kmem_size="20G"
> zfs_load="YES"
>
> OK, what do we do next? :)
>
>
> --
> Regards,
> Doug
>
>