Hi,

I suppose I should create a PR about this. It seems that with 2 gigs of 
memory in use and only a little into swap, the kernel loses its ability to 
allocate memory. This is the third time I've crashed this machine while 
trying to stress test it. NetBSD 2.0.

sd2(esiop0:0:2:0): unable to allocate scsipi_xfer
raid0: IO Error.  Marking /dev/sd2a as failed.
sd2: not queued, error 12
sd2(esiop0:0:2:0): unable to allocate scsipi_xfer
sd2: not queued, error 12
sd1(esiop0:0:1:0): unable to allocate scsipi_xfer
raid0: IO Error.  Marking /dev/sd1a as failed.
sd1: not queued, error 12
raid0: failed to create a dag. Too many component failures. 
...
pool rf_daglist_pl: putting with none out
panic: pool_put
Begin traceback...
0xd5e7bdf0: at pool_do_put+0x2b0
0xd5e7be40: at rf_FreeDAGList+0x18
0xd5e7be50: at rf_FreeRaidAccDesc+0x34
0xd5e7be70: at rf_State_LastState+0x80
0xd5e7be90: at rf_ContinueRaidAccess+0xf0
0xd5e7beb0: at rf_ContinueDagAccess+0x158
0xd5e7bf00: at DAGExecutionThread+0x158
0xd5e7bf40: at cpu_switchto+0x44
0xd5e7bf50: at ADBDevTable+0x73bc8
End traceback...