Subject: [patch 0/6] Guest page hinting version 7.
Date: Friday 27th March 2009 15:09:05 UTC (over 7 years ago)
Greetings, the circus is back in town -- another version of the guest page hinting patches. The patches differ from version 6 only in the kernel version, they apply against 2.6.29. My short sniff test showed that the code is still working as expected. To recap (you can skip this if you read the boiler plate of the last version of the patches): The main benefit for guest page hinting vs. the ballooner is that there is no need for a monitor that keeps track of the memory usage of all the guests, a complex algorithm that calculates the working set sizes and for the calls into the guest kernel to control the size of the balloons. The host just does normal LRU based paging. If the host picks one of the pages the guest can recreate, the host can throw it away instead of writing it to the paging device. Simple and elegant. The main disadvantage is the added complexity that is introduced to the guests memory management code to do the page state changes and to deal with discard faults. Right after booting the page states on my 256 MB z/VM guest looked like this (r=resident, p=preserved, z=zero, S=stable, U=unused, P=potentially volatile, V=volatile):