Subject: change MCLBYTES in kernel
To: None <>
From: Manuel Bouyer <>
List: tech-net
Date: 10/01/2005 16:11:06
for Xen domain0 I'd like to change the mbuf cluster size to 4k (so that
we have only one cluster per page, and it can be swapped with the guest
rather than memcpy'd). It looks like I could use
options MCLSHIFT=12
on i386/conf/XEN0 for this. Any bad side-effect to expect ?
/usr/include/machine/param.h wouldn't match the kernel's idea of MCLBYTES ...

Manuel Bouyer <>
     NetBSD: 26 ans d'experience feront toujours la difference