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Xen Hacker Interviewed
Drawoc Suomynona writes "The Xen virtual monitor is a new generation virtualization software that enable running multiple OSes at the same time with unprecedented level of performances. Manuel Bouyer was recently interviewed about his work porting Xen to the NetBSD operating system. The interview touches on why some consider Xen to be so good, how hard it is to integrate such a software package into an OS, and more."
Linux is STILL for fags.
This red color scheme makes my eyes want to bleed.
Anyways, I skimmed TFA and it's fairly technical. I.E. not your avg interview fluff.
[Fuck Beta]
o0t!
Frist Psot!!1!!
I'm looking for Xen hosting. Who would you recommend and why?
Thanks!
how Xen is different from vmware?
will this be useable to run windows inside OS X ?
if yes, what timeframe are we speaking of then ?
Anyone know Xen compares to jails in, say, FreeBSD? I've managed to setup a jail before where you do a "make world DESTDIR=/jaildir" and then do a jail on that directory, which gives someone the appearance of their own entire operating system. Is Xen similar to this, but allowing for many different operating systems rather than just another instance of the same one?
Also, glad to see the BSD section is at least still around. I can't seem to get it to show up on the Sections list, regardless of how I set it up.
Want to improve your Karma? Instead of "Post Anonymously", try the "Post Humously" option.
I see a ton of comments about not being able to use Xen to run Windows inside Linux, but no information the other way around...
Can Xen run Linux apps on my Windows installation? I am currently using Cygwin for that, and it's working okay, but some of my favorite apps are being run through SSH from my linux box to make all this happen.
I do too much in Windows to even dual-boot the system... I'd spend as much time booting as I would working/playing.
"If you make people think they're thinking, they'll love you; But if you really make them think, they'll hate you." - DM
"Xen also offers virtual machine migration, where you freeze a Xen guest, move it to another machine and resume it there ... This also means that a similar environment for the guest has to exist on the remote system."
And if a similar environment is not available when it is moved, what happens to the state of the user? Would the hardware in use when the state is saved have to be exactly alike on the target machine?
Also, is the information retained on the backup until the full migration is completed and then deleted, or is deleting the backup during the migration optional, leaving a "frozen" and "restorable" state on the server? Is that a security risk if the workstation is compromised?
Stoned4Life
gen = new Random
One more crippling bombshell hit the already beleaguered *BSD community when IDC confirmed that *BSD market share has dropped yet again, now down to less than a fraction of 1 percent of all servers. Coming on the heels of a recent Netcraft survey which plainly states that *BSD has lost more market share, this news serves to reinforce what we've known all along. *BSD is collapsing in complete disarray, as fittingly exemplified by failing dead last in the recent Sys Admin comprehensive networking test.
You don't need to be the Amazing Kreskin to predict *BSD's future. The hand writing is on the wall: *BSD faces a bleak future. In fact there won't be any future at all for *BSD because *BSD is dying. Things are looking very bad for *BSD. As many of us are already aware, *BSD continues to lose market share. Red ink flows like a river of blood.
FreeBSD is the most endangered of them all, having lost 93% of its core developers. The sudden and unpleasant departures of long time FreeBSD developers Jordan Hubbard and Mike Smith only serve to underscore the point more clearly. There can no longer be any doubt: FreeBSD is dying.
Let's keep to the facts and look at the numbers.
OpenBSD leader Theo states that there are 7000 users of OpenBSD. How many users of NetBSD are there? Let's see. The number of OpenBSD versus NetBSD posts on Usenet is roughly in ratio of 5 to 1. Therefore there are about 7000/5 = 1400 NetBSD users. BSD/OS posts on Usenet are about half of the volume of NetBSD posts. Therefore there are about 700 users of BSD/OS. A recent article put FreeBSD at about 80 percent of the *BSD market. Therefore there are (7000+1400+700)*4 = 36400 FreeBSD users. This is consistent with the number of FreeBSD Usenet posts.
Due to the troubles of Walnut Creek, abysmal sales and so on, FreeBSD went out of business and was taken over by BSDI who sell another troubled OS. Now BSDI is also dead, its corpse turned over to yet another charnel house.
All major surveys show that *BSD has steadily declined in market share. *BSD is very sick and its long term survival prospects are very dim. If *BSD is to survive at all it will be among OS dilettante dabblers. *BSD continues to decay. Nothing short of a miracle could save it at this point in time. For all practical purposes, *BSD is dead.
Fact: *BSD is dying
Xen virtual machines can be "live migrated" between physical hosts without stopping them. During this procedure, the memory of the virtual machine is iteratively copied to the destination without stopping its execution. A very brief stoppage of around 60-300 ms is required to perform final synchronisation before the virtual machine begins executing at its final destination, providing an illusion of seamless migration. Similar technology is used to suspend running virtual machines to disk and switch to another virtual machine, and resume the first virtual machine at a later date.
(Quote from Wikipedia)
Reminds of when I was watching the old Max Headroom show, and Max would shuffle himself off of one monitor onto a display on a portable "processing unit" and somebody would pick him up and carry him away.
The higher the technology, the sharper that two-edged sword.
so guest OSes that support that hardware can run with standard drivers. Xen creates a synthetic virtual device that's easier and more efficient to emulate than standard hardware. The downside is that there usually aren't any drivers for these virtual devices on most OSes since no one's written them yet. So if you go on Apple's web site and look for supported video hardware, you probably won't see Xen virtual video device. The other way of looking at it is Xen is the device maker and is supplying the driver directly rather than through Apple. And device makers don't always supply drivers for all OSes, at leat right away.
What I want from OS virtualization is to be able to run one guest OS on multiple hosts for redundency. I don't have (personally) much use for running multiple guest OSs on a host. I want to have a setup where if apache is in the middle of processing a request and a whole machine does, the request is still completed by the remaining machine. RAID1 for the whole damn machine. If you could do this will F/OSS on dirt cheap comodity hardware, the utility would be huge.
"You never know when some crazed rodent with cold feet might be running loose in your pants."
-Calvin
How about vs qemu? It seems Qemu has both a virtualizer and an emulator (the "qemu accelerator does the virtualizer part"), and can run un-modified OS's (like Win2K) just fine in the emulator mode.
I use QEMU quite a bit, to test our stuff on both linux and windwos. (yeh, I used vmware too after they matched qemu in price, and it worked fine too; but I saw no compelling reason to switch)
Curious how Xen compares to teh accelerated QEMU.
Are here and they rock. Zen has been in the making for some time now and is still not production ready. Anyone knows the differences between Zones and Xen?
BTW, Zones give near native performance - verified on production machines.
There's a dude who knows his stuff
Sure his code is interestingly enough
It will fulfill our wettest dreams
Taking multitasking to the extremes
Filling our machines with marshmallow fluff
11. Thou shall obey Da mighty Swing
Xen 3.0 on the newer Intel/AMD chips should be able to run Windows (or any other OS) without modification to the hosted OS.
But will apple support Xen so Mac OS X could be used under Xen? Thus far, I have not heard either yes or no WRT Xen.
I looked this up a while ago... Xen needs the HOST OS to be modified, at least with current CPUs. Fortunately, VMWare player if free as in beer, and it works. So, now I have a perfectly functioning Linux install which I couldn't do before (lack of WiFi support for my wireless chip). Xen is nice, but free VMWare is good and it works.
VMWare ESX Server 3 (currently in beta) will probably get as close as you can to having live fault tolarant servers. By sharing a storage such as SAN or iSCSI, it is able to instantly take over when it detects the failure of another physical box and should not lose any sessions or data. The other cool thing is that it can dynamically move a running virtual machine to a less loaded physical server. Still, it is not running two virtual machines simultaneously like you've described.
It requires changes to the guest Kernel. Dont expect microsoft to do this for us, they have nothing to gain by doing that.
---- Booth was a patriot ----
Yeah, but does it run linux?
Oh wait......
The truth shall always be free: Boris Floricic is Tron.
[ed. note: in the following text, former FreeBSD developer Mike Smith gives his reasons for abandoning FreeBSD]
When I stood for election to the FreeBSD core team nearly two years ago, many of you will recall that it was after a long series of debates during which I maintained that too much organisation, too many rules and too much formality would be a bad thing for the project.
Today, as I read the latest discussions on the future of the FreeBSD project, I see the same problem; a few new faces and many of the old going over the same tired arguments and suggesting variations on the same worthless schemes. Frankly I'm sick of it.
FreeBSD used to be fun. It used to be about doing things the right way. It used to be something that you could sink your teeth into when the mundane chores of programming for a living got you down. It was something cool and exciting; a way to spend your spare time on an endeavour you loved that was at the same time wholesome and worthwhile.
It's not anymore. It's about bylaws and committees and reports and milestones, telling others what to do and doing what you're told. It's about who can rant the longest or shout the loudest or mislead the most people into a bloc in order to legitimise doing what they think is best. Individuals notwithstanding, the project as a whole has lost track of where it's going, and has instead become obsessed with process and mechanics.
So I'm leaving core. I don't want to feel like I should be "doing something" about a project that has lost interest in having something done for it. I don't have the energy to fight what has clearly become a losing battle; I have a life to live and a job to keep, and I won't achieve any of the goals I personally consider worthwhile if I remain obligated to care for the project.
Discussion
I'm sure that I've offended some people already; I'm sure that by the time I'm done here, I'll have offended more. If you feel a need to play to the crowd in your replies rather than make a sincere effort to address the problems I'm discussing here, please do us the courtesy of playing your politics openly.
From a technical perspective, the project faces a set of challenges that significantly outstrips our ability to deliver. Some of the resources that we need to address these challenges are tied up in the fruitless metadiscussions that have raged since we made the mistake of electing officers. Others have left in disgust, or been driven out by the culture of abuse and distraction that has grown up since then. More may well remain available to recruitment, but while the project is busy infighting our chances for successful outreach are sorely diminished.
There's no simple solution to this. For the project to move forward, one or the other of the warring philosophies must win out; either the project returns to its laid-back roots and gets on with the work, or it transforms into a super-organised engineering project and executes a brilliant plan to deliver what, ultimately, we all know we want.
Whatever path is chosen, whatever balance is struck, the choosing and the striking are the important parts. The current indecision and endless conflict are incompatible with any sort of progress.
Trying to dissect the above is far beyond the scope of any parting shot, no matter how distended. All I can really ask of you all is to let go of the minutiae for a moment and take a look at the big picture. What is the ultimate goal here? How can we get there with as little overhead as possible? How would you like to be treated by your fellow travellers?
Shouts
To the Slashdot "BSD is dying" crowd - big deal. Death is part of the cycle; take a look at your soft, pallid bodies and consider that right this very moment, parts of you are dying. See? It's not so bad.
To the bulk of the FreeBSD committerbase and the developer community at large - keep your eyes on the real goals.
Clusters do exactly what you want, seemless failover. Virtualization isn't the term you are loking for.
Xen can essentially do this as well. Simply run a single Xen OS on multiple machines. If one fails then Xen will failit over to another physical machine. You aren't required to run many multiple OSes with Xen.
Most Xen performance numbers that one sees are taken while running in DomainO, not DomainU. Domain0 is going to be using the "native" device drivers ("native", because not using real IRQs, but Xen's Event system). The problem is, that's not where one runs real virtual machines, those are in DomainU's and those have significantly worse performance. an apples vs. oranges comparison is Xen Domain0 vs. Vmware Workstation. an apples to apples in that case is Xen Domain0 (as "host" of DomainUs) vs. Regular Linux (as host of Vmware worksation intances). an apples to apples is also DomainUs vs. Vmware Worksation.
That's not to say, DomainO benchmarks are pointless. In fact, you can do many cool things on Xen that if you don't care about multiple virtual machines, will work in your Domain0 with good performance.
Intel makes the chips. They have said quite clearly that the chips do support VT. People have displayed dmesg's showing that the CPUs do in fact report that they support it. Its just that some companies are shipping shitty boards with the functionality turned off, that doesn't mean that the CPUs don't support it.
. pdf
http://appleintelfaq.com/images/intel_vt_response
a losin6 battle; itself b+ackwards, Fucking numbers, WON'T BE STANDING
I personally have installed and ran generic Windows XP on Xen using the existing Intel chips with VT support. Performance basically sucks right now because Xen currently uses qemu to emulate bios/disk/network/video for these devices so with a lot of disk or network IO you can basically take the machine to its knees because it starts using up 100% cpu to emulate the IO.
This sig will make it clear that ANYONE can use this post for ANY purpose WITHOUT the written consent of the NFL.
Check out OpenBSD's CARP and use for your Apache or other httpd. Complete failover, with no down time if one fails and OpenBSD runs on old, cheap hardware without a hitch. The possibilities are endless! I've seem many great articles on it too. CARP isn't just for redundant firewalls with OpenBSD, it can be used for many other things too.