Tweaking ZFS on FreeBSD 8.2-RELEASE on i386

Having followed the, when configuring ZFS, I was aware of the delicate nature of the kernel settings for ZFS on i386.  I recently upgraded my server to 4GB ECC from 2GB non-ECC and thought I’d like to take advantage of the extra ram, so I thought I’d play around with these options.

My current kernel config could not be simpler, ZFS-GENERIC:

include    GENERIC
ident    ZFS-GENERIC
options    KVA_PAGES=512

For this configuration I successfully used in /boot/loader.conf:

#Working options for ZFS-GENERIC 2GB RAM, KVA_PAGES=512

I thought it would be as simple as:

#Trial options for ZFS-GENERIC 4GB RAM, KVA_PAGES=512

But, but to my chagrin, my system responded on boot up with a:

panic: kmem_suballoc: bad status return of 3

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