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

[Matthew Jacob]

Can you get a stack traceback?

> Hello,
>
> I've got an 8.0-STABLE (amd64) box with 4GB RAM.  The machine is 
> running off a 6-disk RAIDZ1 booting from GPT.  The box consistently 
> panics on unixbench's fsdisk program.
>
> I have been gathering some metrics in an attempt to isolate the 
> parameters that are significant, but I admit I do not really 
> understand all the relationships.  At this point, I have nothing set 
> in /boot/loader.conf
>
> Here are some of the values I was recording within seconds of the panic:
>
> # dmesg | grep memory
> real memory  = 4294967296 (4096 MB)
> avail memory = 3961372672 (3777 MB)
>
> kstat.zfs.misc.arcstats.size: 308522248
> vfs.zfs.arc_max: 829480960
> vfs.zfs.arc_meta_limit: 207370240
> vfs.zfs.arc_meta_used: 165575944
> vfs.zfs.arc_min: 103685120
> vm.kmem_size: 1327169536
> vm.kmem_size_max: 329853485875
>
> # vmstat -m | egrep 'InUse|solaris'
>          Type InUse MemUse HighUse
>       solaris 491349 1316172K       -
>
> % zpool status
>   pool: bethesda
>  state: ONLINE
>  scrub: none requested
> config:
>
>         NAME           STATE     READ WRITE CKSUM
>         bethesda       ONLINE       0     0     0
>           raidz1       ONLINE       0     0     0
>             gpt/disk0  ONLINE       0     0     0
>             gpt/disk1  ONLINE       0     0     0
>             gpt/disk2  ONLINE       0     0     0
>             gpt/disk3  ONLINE       0     0     0
>             gpt/disk4  ONLINE       0     0     0
>             gpt/disk5  ONLINE       0     0     0
>
> errors: No known data errors
>
> My concern is if I can panic the box with a simple file system 
> benchmark, what will happen when I rysnc files across a 1GB LAN 
> connection?   I am very willing to run any number of tests and tweek 
> ZFS as necessary.  Please advise.
>
>