From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Sat, 3 Nov 2012 13:45:55 -0400 From: Kurt H Maier To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net> Message-ID: <20121103174555.GA96072@intma.in> References: <4A0E7310-9D9D-45C5-88A3-62B4A3191267@quintile.net> <20121103163103.GA48522@intma.in> <5cff355142bfe83410dce1c3fc321f25@kw.quanstro.net> <20121103165100.GA63071@intma.in> <7cd2c11374f75d628a5bb5e1f1d0919e@kw.quanstro.net> <20121103171322.GA76929@intma.in> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Subject: Re: [9fans] Kernel panic when allocating a huge memory Topicbox-Message-UUID: d26a6c26-ead7-11e9-9d60-3106f5b1d025 On Sat, Nov 03, 2012 at 01:40:48PM -0400, erik quanstrom wrote: > perhaps my comment about double-swap/paging was not clear > enough. i was considering the hosted os, with some standard > vm such as esxi, vbox, xen or whatever as the host. in such a case it makes > no sense to me for the hosted os to page/swap as the hypervisor > is perfectly capable of doing this itself. in fact, i think having > the guest page/swap while the hypervisor is page/swaping is going > to tend to make things more difficult because of i/o contention, > and the fact that doing i/o tends to temporarly increase memory > use. This makes more sense. However, if your hypervisor is swapping, you've screwed up your planning. RAM oversubscription is the reason most dime-store VPS services suck really badly. I leave swapping to the guest OS, since that's where malloc is being called.