From owner-freebsd-virtualization@FreeBSD.ORG Fri Aug 23 10:30:07 2013 Return-Path: Delivered-To: freebsd-virtualization@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTP id 3324EB67 for ; Fri, 23 Aug 2013 10:30:07 +0000 (UTC) (envelope-from gofd-freebsd-virtualization@m.gmane.org) Received: from plane.gmane.org (plane.gmane.org [80.91.229.3]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id E3EFF2C1D for ; Fri, 23 Aug 2013 10:30:06 +0000 (UTC) Received: from list by plane.gmane.org with local (Exim 4.69) (envelope-from ) id 1VCocu-0005hq-K0 for freebsd-virtualization@freebsd.org; Fri, 23 Aug 2013 12:29:56 +0200 Received: from lara.cc.fer.hr ([161.53.72.113]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Fri, 23 Aug 2013 12:29:56 +0200 Received: from ivoras by lara.cc.fer.hr with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Fri, 23 Aug 2013 12:29:56 +0200 X-Injected-Via-Gmane: http://gmane.org/ To: freebsd-virtualization@freebsd.org From: Ivan Voras Subject: Re: CFT: nested page table integration with amd64/pmap Date: Fri, 23 Aug 2013 12:29:42 +0200 Lines: 44 Message-ID: References: Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="----enig2MXQRQEIRJRXITQDWWTBI" X-Complaints-To: usenet@ger.gmane.org X-Gmane-NNTP-Posting-Host: lara.cc.fer.hr User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:17.0) Gecko/20130322 Thunderbird/17.0.4 In-Reply-To: X-Enigmail-Version: 1.5.1 X-BeenThere: freebsd-virtualization@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: "Discussion of various virtualization techniques FreeBSD supports." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 23 Aug 2013 10:30:07 -0000 This is an OpenPGP/MIME signed message (RFC 4880 and 3156) ------enig2MXQRQEIRJRXITQDWWTBI Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On 23/08/2013 00:55, Neel Natu wrote: > Hi, >=20 > The projects/bhyve_npt_pmap branch modifies the amd64/pmap to be able t= o > deal with Intel EPT mappings in addition to the regular x86 page tables= =2E >=20 > This provides bhyve with the following features: >=20 > 1. Memory overcommit > Guest memory is now pageable and therefore virtual machines can allocat= e > more memory than is physically available on the host. I always wondered about virtualization environments which have pageable guest memory - how does the guest kernel handle situations where it really needs non-pageable memory? Does is simply "not care" because for it the memory access looks just like it isn't paged but is simply very, very slow? What about time-sensitive situations (like the originally mentioned PCI-passthrough)? ------enig2MXQRQEIRJRXITQDWWTBI Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.19 (FreeBSD) Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iEYEARECAAYFAlIXOZgACgkQ/QjVBj3/HSyYgACfWA9NPNFPLYXIN6ijqvyFaZxe QHQAoI0xT/PjHIGqddUrZ4HMZU+MJgcy =ptsi -----END PGP SIGNATURE----- ------enig2MXQRQEIRJRXITQDWWTBI--