Re: putting fedora on a (memory) diet... some suggestions for the kernel config

[Bill Nottingham <notting redhat com>]

Arjan van de Ven (arjan fenrus demon nl) said: 
> Another one is __log_buf; this is currently 128Kb. Arguably it's
> important for debugging to get 128Kb of dmesg info, but I wonder if 64Kb
> would be enough as well, it's another easy save by setting
> CONFIG_LOG_BUF_SHIFT to 16.

64k of savings I'm not sure is enough - you can get more by whacking
userspace. The 2+MB from NR_CPUS looks worthwhile.

> A third one is disabling CPU hotplug. CPU hotplug keeps quite a bit of
> code in the kernel, that otherwise is boot-time only and gets evicted
> right after boot..... You could argue the same for PCI hotplug but
> cardbus is sort of the party spoiler there I suppose.

Xen and other virt stuff trips you up here.

Bill