Re: Small address spaces patch for Xen

[Jacob Gorm Hansen <jacobg@diku.dk>]

Jacob Gorm Hansen wrote:
> Hi,
> 
> attached is my patch for xen and xenlinux to enable small address 
> spaces. To use this, you will need a purpose-built user space for dom0, 
> available through the link below. Unpack this in an empty partition, on 
> a ramdisk, or export it as an nfsroot. Remember to add init=/linuxrc to 
> your dom0 kernel commandline.
> 

And by the way, if you have HT please remember to run xen with the 
'noht' option if you want to see anything change.

Also, in xen/arch/x86/domain.c, if you #define the symbol SW_PERF, you 
will get periodic printk's telling you how many TLB flushes you save 
with this print:

printk("tot %d free %d update %d flush %d\n",sw_total, sw_free, 
sw_update, sw_flush);

'tot' is the total amount of context switches, 'update' is the number of 
pgd-cache updates (memcpys), and 'flush' is the total amount of TLB flushes.

'free' is total/2, and not really interesting as the other half is also 
free.

Jacob