Messages in this thread | | | Date | Sun, 23 Dec 2007 20:11:49 -0500 | From | Rik van Riel <> | Subject | Re: [patch 00/20] VM pageout scalability improvements |
| |
On Mon, 24 Dec 2007 04:29:36 +0530 Balbir Singh <balbir@linux.vnet.ibm.com> wrote: > Rik van Riel wrote:
> > In the real world, users with large JVMs on their servers, which > > sometimes go a little into swap, can trigger this system. All of > > the CPUs end up scanning the active list, and all pages have the > > referenced bit set. Even if the system eventually recovers, it > > might as well have been dead. > > > > Going into swap a little should only take a little bit of time. > > Very fascinating, so we need to scale better with larger memory. > I suspect part of the answer will lie with using large/huge pages.
Linus vetoed going to a larger soft page size, with good reason.
Just look at how much the 64kB page size on PPC64 sucks for most workloads - it works for PPC64 because people buy PPC64 monster systems for the kinds of monster workloads that work well with a large page size, but it definately isn't general purpose.
| |