FreeBSD 7b3 - ZFS crashes

[Mark Kirkwood]

Stefan Huerter wrote:
> Hello
>
> Just testing the new FB 7beta3 - installed from the ISO-images.
> System is running on an SCSI 9GB disk, the machine has 750MHz with 
> 512MB Ram and the zfs is using 8 ATA Disks, 4x120GB and 4x160GB 
> connected to Promise Fasttrak TX2 (with no configs).
> Creating the ZFS using "zpool create tank raidz adX" was fascinating, 
> after a few seconds I have 920GB disk space - WoW.
> kmem_min is 256MB.
>
> Next step was creating /tank/CTM and /tank/CVS, then running 
> pwd:/tank/CVS/ctm -vvv /tank/CTM/* and while extracting it suddenly 
> hangs.
>
> Nice: I can login in new sessions.
> Bad: Systems hangs, sync runs in nirwana and trying to reboot produces 
> "Deadly processes found, won't die" and hangs up the reboot.
>
>

See: http://wiki.freebsd.org/ZFSTuningGuide

However - as you have 512Mb of RAM you can't really take up the 
suggestions there. I'm trying zfs out on a 2xPIII 1.26Ghz with 2G of RAM 
- and even after fooling about with custom kernels that have increased 
KVA_PAGES... I can't get the zfs buffer cache to use any more than 600Mb 
of (kernel) memory. It is however stable... so more memory helps!

Any chance of you finding any more RAM for the box?

Cheers

Mark