Tuning KVA_PAGES / kmem?

Ruslan Ermilov ru at freebsd.org
Tue Apr 20 06:40:23 PDT 2004

On Tue, Apr 20, 2004 at 01:14:52PM +0200, Stefan Bethke wrote:
> Hi,
> I'm struggling a bit with a box I'm setting up right now: 2x Xeon 2.8  
> GHz with 6 GB RAM. Main disk is a RAID 5 on 3ware controller. I'm  
> running -current from around Easter.
> Occasionally, the machine panics with:
> panic: kmem_malloc(4096): kmem_map too small: 275251200 total allocated
> at line 337 in file /usr/src/sys/vm/vm_kern.c
> I had stability problems when I was using PAE, so I disabled that for  
> the moment; even when running GENERIC, I get this panic.
> I dug through the archives, and I found some hints that with >>2 GB  
> RAM, the auto-tuning might produce undesirable results, so I might need  
> to tune KVA_PAGES to reserve more address space for the kernel, or  
> fiddle with VM_KMEM_SIZE_MAX, VM_KMEM_SIZE_SCALE, or some vm sysctls.
> Can someone point me in the right direction?
See sys/i386/conf/NOTES, when it talks about KVA_PAGES, for the

Ruslan Ermilov
ru at FreeBSD.org
FreeBSD committer
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 187 bytes
Desc: not available
Url : http://lists.freebsd.org/pipermail/freebsd-current/attachments/20040420/83dbc533/attachment.bin

More information about the freebsd-current mailing list