Adam Litke <alitke@xxxxxxxxxx> writes: > On 20/02/14 14:53 +1030, Rusty Russell wrote: >>I think we're headed to the same destination here; the variant which I >>came up with (and suggested to Daniel and Luiz, CC'd) is similar: the >>guest self-balloons, giving up pages when it can, but the host sets a >>ceiling. >> >>This way, if the host really needs to set a limit, it can: a disobedient >>guest will start paging. But generally, a guest should use its >>judgement to balloon its own pages as it can (below the ceiling). > > It sounds similar but it sounds like you are suggesting one limit > value and I am suggesting two. Your ceiling value sounds like a soft > limit on total guest memory (aka minimum balloon size). This is the > more important limit of the two I have suggested. Do you think it's > also worthwhile to have a maximum balloon size (floor value) to keep > the allowable balloon size between two points? It's a little simpler to have a ceiling only. And if everyone (guests and host) are feeling like they have plenty of memory, it's probably best sitting in the host. 1) It can quickly go to a guest if necessary. 2) The host could coalesce/shuffle memory. 3) The host could turn off RAM to save power. Cheers, Rusty. _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization
