LWN: Comments on "Virtual machines as containers"

Virtual machines as containers

hansendc — Thu, 28 Apr 2016 20:58:52 +0000

Pages in CleanCache are not *usable*. The data has to be pulled out of CleanCache (and duplicated) before it can actually be used by a guest. So while CleanCache is an improvement over simply throwing data away, it is pretty inferior to mechanisms that allow the page to be both used and shared at the same time.

Virtual machines as containers

eternaleye — Thu, 28 Apr 2016 18:00:58 +0000

Isn't this exactly a use case of CleanCache and FrontSwap - one of the ones explicitly described in their rationale prior to their being merged? ISTR a paravirt driver for them that _really did_ push pagecache pages (for CleanCache) and anonymous pages (for FrontSwap) to the host...