From: Andy E. <and...@pa...> - 2002-11-20 07:20:55
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Hi all. I'm a newcomer to UML but a very keen follower of its progress :-) . One thing I was wondering is - is it possible to run UML on top of "Bochs" ( the operating system emulator)? I searched the UML site for any mention of Bochs , but didn't find anything. So, has anyone out there had a go at running UML on Bochs (and is it actually possible to do this? ). Many thanks in advance ! - Andy |
From: Matthew B. <ma...@by...> - 2002-11-20 08:10:49
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On Wednesday 20 November 2002 07:20, Andy Elvey wrote: > Hi all. I'm a newcomer to UML but a very keen follower of its progress > > :-) . > > One thing I was wondering is - is it possible to run UML on top of > "Bochs" ( the operating system emulator)? Given that Bochs boots Linux without problems last time I looked, I don't see why it wouldn't run UML. I'm not even going to begin to ask why :) -- Matthew Bloch Bytemark Computer Consulting Limited http://www.bytemark.co.uk/ tel. +44 (0) 8707 455026 |
From: Steve S. <sn...@fr...> - 2002-11-20 08:53:08
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On Wed, Nov 20, 2002 at 08:13:54AM +0000, Matthew Bloch wrote: > > One thing I was wondering is - is it possible to run UML on top of > > "Bochs" ( the operating system emulator)? > Given that Bochs boots Linux without problems last time I looked, I don't see > why it wouldn't run UML. I'm not even going to begin to ask why :) Short answer : UML on top of Bochs : No UML on top of Linux on top of Bochs : Yes Long answer : UML doens't know anything about hardware, since it relies on a underlying linux kernel to talk to real hardware. Since Bochs only provides virtual 'hardware', UML wouldn't know how to use it. [ for Linux a IDE interface is a I/O port, for UML it is a file from the host kernel ] So, UML won't run directly, u have to use a Linux kernel in the middle. [ this could lead to an easy porting, albeit not optimally at all, UML to virtually any platform that Bochs runs on ] PS: as usual, if i'm wrong, please correct me ;-) Steve -- GPG public key available from http://snide.free.fr/gpg/snide-free.fr.asc Or by email to "snide at free.fr" with "send key pub" as subject Fingerprint: 91E3 C5F1 2641 4D0F EDD0 7116 D187 5929 14A8 FDA2 |
From: Steve S. <sn...@fr...> - 2002-11-20 09:07:58
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On Wed, Nov 20, 2002 at 09:52:31AM +0100, Steve Schnepp wrote: > On Wed, Nov 20, 2002 at 08:13:54AM +0000, Matthew Bloch wrote: > > > One thing I was wondering is - is it possible to run UML on top of > > > "Bochs" ( the operating system emulator)? Actually, Bochs isn't exactly an "OS" emulator, it's more an IA-32 architecture hardware emulator. That's why UML won't work directly on it, but an Operating System yes. Steve -- GPG public key available from http://snide.free.fr/gpg/snide-free.fr.asc Or by email to "snide at free.fr" with "send key pub" as subject Fingerprint: 91E3 C5F1 2641 4D0F EDD0 7116 D187 5929 14A8 FDA2 |
From: Nathan <ch...@st...> - 2002-11-20 16:41:53
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Hi all, I've been bashing my head out trying to get some kind of networking working under UML. Because we're standardising on RedHat in our company (sigh) I've tried to follow the guide to setting up RedHat. I've also tried the main networking guide on the UML site. I've compiled a 2.4.19+skas host kernel and a 2.4.19 UML kernel, and all the UML utils. The kernel boots, seems to go through all the initialisation options, but when it gets to the networking part of the RedHat installer, it can never do DHCP and I can't assign it an address. Same thing happens if I try one of the pre-made system images. Can anyone give me a step-by-step rundown of exactly what commands to type to get a second interface on the host machine that is bound to the UML instance that would allow it to DHCP or at least assign an IP? ie, if I need a br0, what do I type on the host, and what kernel options need to be compiled in (I'm assuming TUN/TAP and ethernet bridging, etc, but is there anything else?) I really would like to see UML the basis of our hosting platform, but unless we can get networking working, it will be useless. Any help would be appreciated. Regards, Nathan. -- "The person who stands up and says, 'This is stupid,' either is asked to 'behave' or, worse, is greeted with a cheerful 'Yes, we know! Isn't it terrific!'." - Frank Zappa |
From: Net L. <net...@li...> - 2002-11-20 16:55:13
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See http://sxs.sf.net/sxs/uml.html On Thu, 21 Nov 2002, Nathan wrote: > Hi all, > > I've been bashing my head out trying to get some kind of networking > working under UML. > > Because we're standardising on RedHat in our company (sigh) I've tried > to follow the guide to setting up RedHat. I've also tried the main > networking guide on the UML site. > > I've compiled a 2.4.19+skas host kernel and a 2.4.19 UML kernel, and > all the UML utils. The kernel boots, seems to go through all the > initialisation options, but when it gets to the networking part of the > RedHat installer, it can never do DHCP and I can't assign it an > address. Same thing happens if I try one of the pre-made system images. > > Can anyone give me a step-by-step rundown of exactly what commands to > type to get a second interface on the host machine that is bound to the > UML instance that would allow it to DHCP or at least assign an IP? ie, > if I need a br0, what do I type on the host, and what kernel options > need to be compiled in (I'm assuming TUN/TAP and ethernet bridging, > etc, but is there anything else?) > > I really would like to see UML the basis of our hosting platform, but > unless we can get networking working, it will be useless. > > Any help would be appreciated. > > Regards, > > Nathan. > > -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Lonni J Friedman net...@li... Linux Step-by-step & TyGeMo http://netllama.ipfox.com |
From: Andy E. <and...@pa...> - 2002-11-21 07:01:46
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Steve Schnepp wrote: >On Wed, Nov 20, 2002 at 08:13:54AM +0000, Matthew Bloch wrote: > > >>> One thing I was wondering is - is it possible to run UML on top of >>>"Bochs" ( the operating system emulator)? >>> >>> >>Given that Bochs boots Linux without problems last time I looked, I don't see >>why it wouldn't run UML. I'm not even going to begin to ask why :) >> >> > >Short answer : >UML on top of Bochs : No >UML on top of Linux on top of Bochs : Yes > >Long answer : >UML doens't know anything about hardware, since it relies on a >underlying linux kernel to talk to real hardware. Since Bochs only >provides virtual 'hardware', UML wouldn't know how to use it. >[ for Linux a IDE interface is a I/O port, for UML it is a file from the >host kernel ] > >So, UML won't run directly, u have to use a Linux kernel in the middle. >[ this could lead to an easy porting, albeit not optimally at all, UML to >virtually any platform that Bochs runs on ] > >PS: as usual, if i'm wrong, please correct me ;-) > > Steve > > Thanks very much for your reply, Steve ! ( and also thanks to Matthew Bloch ) . UML looks to be making great progress - very keen to start using it myself ... :-) . - Andy |
From: Snoopy <sn...@do...> - 2002-11-22 15:21:21
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Dear List, as we are thinking about using UML commercially I was wondering if you users out there could give me some idea of how many maximum UMLs we can run on a piece of hardware. We are thinking of hosting it on 2x1.3 Ghz Pentium IIIs, 4 Gig of RAM, 2x120 GB disks. Does anyone out there run UML on similar hardware and could you let me know how many you run with acceptable response time on your hardware ? I am not really looking at hard limits, but kind of things like "after 60 performance goes downhill" etc. etc. Of course it would be good, if you let me know how you invoke the UMLs i.e. what RAM parameter you give them etc. Does anyone have experiences with overcommitting resources, i.e. what happens if the sum of all running UMLs mem parameters exceeds physical RAM for example ? I will gladly post a summary to the list. Love, Snoopy |
From: Net L. <net...@li...> - 2002-11-22 15:32:55
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On Fri, 22 Nov 2002, Snoopy wrote: > as we are thinking about using UML commercially I was wondering if you > users out there could give me some idea of how many maximum UMLs we can > run on a piece of hardware. > > We are thinking of hosting it on 2x1.3 Ghz Pentium IIIs, 4 Gig of RAM, > 2x120 GB disks. > > Does anyone out there run UML on similar hardware and could you let me > know how many you run with acceptable response time on your hardware ? It really depends on what you're going to run inside the UML instances. I've got two UML servers, each a quad Xeon 700Mhz, with 4GB RAM, and 6GB swap, and about 850GB storage. RAM is almost always the limiting factor for UML, unless you're going to run CPU intensive apps inside UML. With the hardware i've listed, i've found about 20 simultaneous UML's as the limit before the load on the physical server starts to get above about 1.50/cpu. I'm running apache, exim, cvs, ldap & PostgreSQL inside my UMLs. > > I am not really looking at hard limits, but kind of things like "after > 60 performance goes downhill" etc. etc. > > Of course it would be good, if you let me know how you invoke the UMLs > i.e. what RAM parameter you give them etc. > > Does anyone have experiences with overcommitting resources, i.e. what > happens if the sum of all running UMLs mem parameters exceeds physical > RAM for example ? About the same thing that happens on a physical box when you've consumed all of your physical + swap. THe kernel starts killing processes. It ain't pretty. -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Lonni J Friedman net...@li... Linux Step-by-step & TyGeMo http://netllama.ipfox.com |
From: Lars Marowsky-B. <lm...@su...> - 2002-11-22 16:34:57
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On 2002-11-22T10:32:42, Net Llama! <net...@li...> said: > It really depends on what you're going to run inside the UML instances. > I've got two UML servers, each a quad Xeon 700Mhz, with 4GB RAM, and 6GB > swap, and about 850GB storage. RAM is almost always the limiting factor > for UML, unless you're going to run CPU intensive apps inside UML. With > the hardware i've listed, i've found about 20 simultaneous UML's as the > limit before the load on the physical server starts to get above about > 1.50/cpu. I'm running apache, exim, cvs, ldap & PostgreSQL inside my > UMLs. Is this with or without the ska patches on the host yet? Sincerely, Lars Marowsky-Brée <lm...@su...> -- Principal Squirrel SuSE Labs - Research & Development, SuSE Linux AG "If anything can go wrong, it will." "Chance favors the prepared (mind)." -- Capt. Edward A. Murphy -- Louis Pasteur |
From: Net L. <net...@li...> - 2002-11-22 16:40:13
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On Fri, 22 Nov 2002, Lars Marowsky-Bree wrote: > On 2002-11-22T10:32:42, > Net Llama! <net...@li...> said: > > > It really depends on what you're going to run inside the UML instances. > > I've got two UML servers, each a quad Xeon 700Mhz, with 4GB RAM, and 6GB > > swap, and about 850GB storage. RAM is almost always the limiting factor > > for UML, unless you're going to run CPU intensive apps inside UML. With > > the hardware i've listed, i've found about 20 simultaneous UML's as the > > limit before the load on the physical server starts to get above about > > 1.50/cpu. I'm running apache, exim, cvs, ldap & PostgreSQL inside my > > UMLs. > > Is this with or without the ska patches on the host yet? Without. I'm running the stock 2.4.18-36 kernel that Jeff provides. -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Lonni J Friedman net...@li... Linux Step-by-step & TyGeMo http://netllama.ipfox.com |
From: Steve S. <sn...@fr...> - 2002-11-22 16:00:55
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On Fri, Nov 22, 2002 at 04:22:24PM +0100, Snoopy wrote: > as we are thinking about using UML commercially I was wondering if you > users out there could give me some idea of how many maximum UMLs we can > run on a piece of hardware. As David C. said, it depends really much on the RAM of the server. > Does anyone out there run UML on similar hardware and could you let me > know how many you run with acceptable response time on your hardware ? Just have a look at the different hosting plateform of David C. and Bill > I am not really looking at hard limits, but kind of things like "after > 60 performance goes downhill" etc. etc. The basic rule is : Physical RAM > n * UML RAM + Host usage Since when a UML starts to swap agressively, usually it will be worse soon. > Of course it would be good, if you let me know how you invoke the UMLs > i.e. what RAM parameter you give them etc. Depends on what ur consumer will do with it. [ a good idea is to fix a entry fee with let's say 32M, and heve the consumer to pay extra for each extra 4M ] I also think that allowing the UML to swap is bad for colocating, since I/O is a weak point in linux, since the impact is not proportional. That's why i really thing that RAM usage is much more important than HDD usage. If an UML or the host starts to swap, u'r in big trouble.. [ the performance will drop drastictly... remember that HDD is more than 1000 times slower than RAM ] > Does anyone have experiences with overcommitting resources, i.e. what > happens if the sum of all running UMLs mem parameters exceeds physical > RAM for example ? The same than when a normal host run out of RAM and starts to swap agressively.. So what happens ? nothing good.. i mean, not something that ur consumers are ready to accept ;-) > I will gladly post a summary to the list. ;-) Steve -- GPG public key available from http://snide.free.fr/gpg/snide-free.fr.asc Or by email to "snide at free.fr" with "send key pub" as subject Fingerprint: 91E3 C5F1 2641 4D0F EDD0 7116 D187 5929 14A8 FDA2 |