Re: [Qemu-devel] [PATCHv4 0/9] buffer_is_zero / migration optimizations

[Paolo Bonzini]

> ubuntu 12.04 LTS 64-bit desktop with 1G memory shortly after boot:
> histogram: 31.7% 32.9% [...] 36.4% 100.0%
> 
> ---
> 
> opensuse 11.1 64-bit with 24GB ram (busy server)
> histogram: 97.5% 97.9% [...] 99.5% 100.0%
> 
> ---
> 
> windows server 2008 R2 with 8G ram running for 3 days:
> histogram:  20.9% 21.3% [...] 22.5% 100.0%
> 
> ---
> 
> windows XP guest with 1G Ram running for approx. 1 hours
> histogram: 25.6% [...] 35.8% 100.0%

Doesn't this suggest checking the first _and the last_ word,
and using the vectorized loop if none is zero?

Paolo