kmem_malloc(4096): kmem_map too small: 536870912 total allocated

[Vladimir Sharun]

We have 2xOpteron/2Gb RAM server with extrensive disk load. Every week or two
it suddenly hangs with "kmem_malloc(4096): kmem_map too small 335bla-bla allocated". 
I look onto handbook and put vm.kmem_size_max="536870912" onto /boot/loader.conf.
Today was the same with the new parameters. Is there any other solutions ?

# sysctl -a | grep kmem
vm.kmem_size: 536870912
vm.kmem_size_max: 536870912
vm.kmem_size_scale: 3

The only vm.kmem_size_max on loader.conf, no vm.kmem_size.

We're running FreeBSD 6.0-BETA5 #0: Wed Sep 28 16:54:33 EEST 2005
in i386 mode. The same was with 5.3/5.4 and NetBSD 2.0 on this machine.