Hi, I was considering installing a minimal Fedora 8 setup with the Xen kernel and then performing most of my work in several different DomUs (perhaps Fedora of Ubuntu) as well as running Windows in a VMware setup (don''t currently have hardware virtualization support). Note that this is on a laptop. Are there any specific issues that I should be aware of (such as suspend/resume issues, etc.) and does anyone have any specific recommendations? Thank you for your help. -- Mathew Brown mathewbrown@fastmail.fm -- http://www.fastmail.fm - Access your email from home and the web
Richard W.M. Jones
2007-Nov-13 11:33 UTC
Re: [Fedora-xen] Minimal Fedora 8 Xen Setup for Laptop
Mathew Brown wrote:> Hi, > I was considering installing a minimal Fedora 8 setup with the Xen > kernel and then performing most of my work in several different DomUs > (perhaps Fedora of Ubuntu) as well as running Windows in a VMware > setup (don''t currently have hardware virtualization support). Note > that this is on a laptop. Are there any specific issues that I should > be aware of (such as suspend/resume issues, etc.) and does anyone have > any specific recommendations? Thank you for your help.Xen and laptops aren''t really friends with each other. In particular power management doesn''t work so the laptop will run hot and eat batteries, suspend/resume are unlikely to work, and so on. Also it''s difficult to mix different hypervisors. I don''t think you can run Xen & VMWare at the same time. Have you thought about using qemu instead? A QEmu guest is just an ordinary Linux process, so much more predictable. It''s a shame that your laptop doesn''t have HVM. What is the processor? Rich. -- Emerging Technologies, Red Hat - http://et.redhat.com/~rjones/ Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SL4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 03798903
On Tue, 13 Nov 2007 11:33:13 +0000, "Richard W.M. Jones" <rjones@redhat.com> said:> Mathew Brown wrote: > > Hi, > > I was considering installing a minimal Fedora 8 setup with the Xen > > kernel and then performing most of my work in several different DomUs > > (perhaps Fedora of Ubuntu) as well as running Windows in a VMware > > setup (don''t currently have hardware virtualization support). Note > > that this is on a laptop. Are there any specific issues that I should > > be aware of (such as suspend/resume issues, etc.) and does anyone have > > any specific recommendations? Thank you for your help. > > Xen and laptops aren''t really friends with each other. In particular > power management doesn''t work so the laptop will run hot and eat > batteries, suspend/resume are unlikely to work, and so on.I remember on the Xen mailing list that they wanted to encourage people to start using Xen on laptops to help troubleshoot power management related issues.> Also it''s difficult to mix different hypervisors. I don''t think you can > run Xen & VMWare at the same time. > > Have you thought about using qemu instead? A QEmu guest is just an > ordinary Linux process, so much more predictable. It''s a shame that > your laptop doesn''t have HVM. What is the processor?I just rechecked. I have the HP nc6320 and just came across a post that says that they released a BIOS update to enable virtualization :) I hope to try it out. But even then, how stable is Windows under Xen (I plan on running a lot of appliactions and trying to port my current Windows setup + applications to it). I was planning on using P2V and make a VMware virtual machine image of my current setup and then use that under VMware. That would definitely be the easier approach. Also, Qemu is very very slow. VirtualBox is a better approach. However, neither VirtualBox or Qemu are really what I''m looking at (I''ve used both in the past). Thanks for your help.> Rich. > > -- > Emerging Technologies, Red Hat - http://et.redhat.com/~rjones/ > Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod > Street, Windsor, Berkshire, SL4 1TE, United Kingdom. Registered in > England and Wales under Company Registration No. 03798903-- Mathew Brown mathewbrown@fastmail.fm -- http://www.fastmail.fm - The professional email service
Daniel P. Berrange
2007-Nov-14 16:01 UTC
Re: [Fedora-xen] Minimal Fedora 8 Xen Setup for Laptop
On Wed, Nov 14, 2007 at 07:58:55AM -0800, Mathew Brown wrote:> > On Tue, 13 Nov 2007 11:33:13 +0000, "Richard W.M. Jones" > <rjones@redhat.com> said: > > Mathew Brown wrote: > > > Hi, > > > I was considering installing a minimal Fedora 8 setup with the Xen > > > kernel and then performing most of my work in several different DomUs > > > (perhaps Fedora of Ubuntu) as well as running Windows in a VMware > > > setup (don''t currently have hardware virtualization support). Note > > > that this is on a laptop. Are there any specific issues that I should > > > be aware of (such as suspend/resume issues, etc.) and does anyone have > > > any specific recommendations? Thank you for your help. > > > > Xen and laptops aren''t really friends with each other. In particular > > power management doesn''t work so the laptop will run hot and eat > > batteries, suspend/resume are unlikely to work, and so on. > > I remember on the Xen mailing list that they wanted to encourage people > to start using Xen on laptops to help troubleshoot power management > related issues.There''s no troubleshooting to be done. It is quite simply not implemented. There is no suspend/hibernate support. CPU scaling is useless because Dom0 can''t neccessarily see all physical CPUs, and has no info about the activity of the guest. The split Dom0/HV architecture is a loosing battle for ths kind of stuff which is why we recoomend KVM as the only viable solution for laptops. Dan. -- |=- Red Hat, Engineering, Emerging Technologies, Boston. +1 978 392 2496 -=| |=- Perl modules: http://search.cpan.org/~danberr/ -=| |=- Projects: http://freshmeat.net/~danielpb/ -=| |=- GnuPG: 7D3B9505 F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 -=|
Thanks for the clarification. My bad :) Also, if it was a minimal xen kernel and I had the DomU''s running, I should be able to use save/restore on the DomUs (where I would be doing 90%+ of my typical work) to simulate suspending. On Wed, 14 Nov 2007 16:01:22 +0000, "Daniel P. Berrange" <berrange@redhat.com> said:> On Wed, Nov 14, 2007 at 07:58:55AM -0800, Mathew Brown wrote: > > > > On Tue, 13 Nov 2007 11:33:13 +0000, "Richard W.M. Jones" > > <rjones@redhat.com> said: > > > Mathew Brown wrote: > > > > Hi, > > > > I was considering installing a minimal Fedora 8 setup with the Xen > > > > kernel and then performing most of my work in several different DomUs > > > > (perhaps Fedora of Ubuntu) as well as running Windows in a VMware > > > > setup (don''t currently have hardware virtualization support). Note > > > > that this is on a laptop. Are there any specific issues that I should > > > > be aware of (such as suspend/resume issues, etc.) and does anyone have > > > > any specific recommendations? Thank you for your help. > > > > > > Xen and laptops aren''t really friends with each other. In particular > > > power management doesn''t work so the laptop will run hot and eat > > > batteries, suspend/resume are unlikely to work, and so on. > > > > I remember on the Xen mailing list that they wanted to encourage people > > to start using Xen on laptops to help troubleshoot power management > > related issues. > > There''s no troubleshooting to be done. It is quite simply not > implemented. > There is no suspend/hibernate support. CPU scaling is useless because > Dom0 can''t neccessarily see all physical CPUs, and has no info about the > activity of the guest. > > The split Dom0/HV architecture is a loosing battle for ths kind of stuff > which is why we recoomend KVM as the only viable solution for laptops. > > Dan. > -- > |=- Red Hat, Engineering, Emerging Technologies, Boston. +1 978 392 2496 > -=| > |=- Perl modules: http://search.cpan.org/~danberr/ > -=| > |=- Projects: http://freshmeat.net/~danielpb/ > -=| > |=- GnuPG: 7D3B9505 F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 > -=|-- Mathew Brown mathewbrown@fastmail.fm -- http://www.fastmail.fm - A fast, anti-spam email service.
Richard W.M. Jones
2007-Nov-14 16:21 UTC
Re: [Fedora-xen] Minimal Fedora 8 Xen Setup for Laptop
Mathew Brown wrote:> On Tue, 13 Nov 2007 11:33:13 +0000, "Richard W.M. Jones" > <rjones@redhat.com> said: >> Have you thought about using qemu instead? A QEmu guest is just an >> ordinary Linux process, so much more predictable. It''s a shame that >> your laptop doesn''t have HVM. What is the processor? > > > I just rechecked. I have the HP nc6320 and just came across a post that > says that they released a BIOS update to enable virtualization :)This isn''t uncommon. Most BIOSes disable virtualization at boot time by writing to a processor-specific register (which, on Intel, cannot be unset without booting). This is a security feature to stop a particular form of near undetectable rootkit. So you need BIOS support and this is commonly supplied through BIOS upgrades - eg. Lenovo did this for the Thinkpad models which support HVM.> hope to try it out. But even then, how stable is Windows under Xen (IXen upstream certainly support Windows under Xen. Of course you absolutely do need hardware virt support in your processor. It may not surprise you to know that we don''t use very much Windows round here, so I can''t personally comment on how well it works. Rich. -- Emerging Technologies, Red Hat - http://et.redhat.com/~rjones/ Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SL4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 03798903
Hi Richard, Just out of curiosity. How is running VMware different from running Qemu with kqemu? From my understanding, both of them rely on a kernel driver (or more than one) and a process running. So why shouldn''t running vmware server under a Xen Dom0 works? Thanks for your help. On Wed, 14 Nov 2007 16:21:21 +0000, "Richard W.M. Jones" <rjones@redhat.com> said:> Mathew Brown wrote: > > On Tue, 13 Nov 2007 11:33:13 +0000, "Richard W.M. Jones" > > <rjones@redhat.com> said: > >> Have you thought about using qemu instead? A QEmu guest is just an > >> ordinary Linux process, so much more predictable. It''s a shame that > >> your laptop doesn''t have HVM. What is the processor? > > > > > > I just rechecked. I have the HP nc6320 and just came across a post that > > says that they released a BIOS update to enable virtualization :) > > This isn''t uncommon. Most BIOSes disable virtualization at boot time by > writing to a processor-specific register (which, on Intel, cannot be > unset without booting). This is a security feature to stop a particular > form of near undetectable rootkit. So you need BIOS support and this is > commonly supplied through BIOS upgrades - eg. Lenovo did this for the > Thinkpad models which support HVM. > > > hope to try it out. But even then, how stable is Windows under Xen (I > > Xen upstream certainly support Windows under Xen. Of course you > absolutely do need hardware virt support in your processor. It may not > surprise you to know that we don''t use very much Windows round here, so > I can''t personally comment on how well it works. > > Rich. > > -- > Emerging Technologies, Red Hat - http://et.redhat.com/~rjones/ > Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod > Street, Windsor, Berkshire, SL4 1TE, United Kingdom. Registered in > England and Wales under Company Registration No. 03798903-- Mathew Brown mathewbrown@fastmail.fm -- http://www.fastmail.fm - A fast, anti-spam email service.