Vertuozzo vs UML
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Q. How fast are your VPSs?
A. Our VPSs are the fastest in the industry. We run the Virtuozzo Linux kernel, which provides VPS services within kernel mode, the same way VPS services are offered on mainframe operating systems that pioneered this technology.
Anyone claiming to offer VPS services using, for example, UserMode Linux (UML) or VMWare, are not offering a true VPS. These systems run the VPS in user-mode, which takes a significant performance hit since every system call goes through a user-mode abstraction layer -- that sucks!
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I would be interested in a technical evaluation of this answer from someone from linode and/or anyone competent to do so.
I am more interested in an evaluation of each from a performance standpoint rather than getting hung up on what deserves to be called a "true VPS" or not.
Thanks,
Mark
9 Replies
Another point as it applies directly to Linode is the number of users on a single host. Christ doesn't over sell a particular host server as is very common in the hosting industry. In fact when he was working through some performace problems he even under-sold the hosts to ensure a higl level of service. I believe there is still an offer for a full refund in 7 days or some such if you aren't satisfied. You should check it out, you might be suprised
caker
Linode Staff
Here's a post you might be interested in:
UML does have a performance hit. There are other advantages to UML, so it depends on what you're after.
-Chris
I am not sure how a 'system call' would be defined in this context. Does accessing the file system involve system calls for this purpose?
Specifically does something like opening a connection to a MySQL database and reading records from it occur on top of the abstraction layer or rather is it the kind of thing that suffers performance wise under UML?
caker
Linode Staff
@mark100net:
I am not sure how a 'system call' would be defined in this context. Does accessing the file system involve system calls for this purpose?
System calls are made when accessing resources that the kernel is responsible for. So yes, accessing the filesystem, or creating a network socket would generate calls into the kernel.
If you strace a process it will show you the system calls it makes … for example "strace ls /" would show you the system calls involved in executing "ls" against the root directory…
OTOH, all the logic and code inbetween each system call runs at full steam.
Virtuozzo is pretty expensive -- that means either the extra costs are transferred to the end-customers, or the servers are loaded up to compensate. One could argue there is less overhead with Virtuozzo therefore they can fit more users onto a machine, but that increases the number of customers potentially sucking up resources away from you.
If one's only requirement is performance, they should be looking at dedis anyhow…
-Chris
> Christ doesn't over sell a particular host server as is very common in the hosting industry
I am assuming that's a typo - unless you're trying to flatter Chris in the biggest way possible
@probonic:
> Christ doesn't over sell a particular host server as is very common in the hosting industryI am assuming that's a typo - unless you're trying to flatter Chris in the biggest way possible
:lol:
I'm not seeing a typo there.
I had a site hosted with a standard web hosting provider and a quick look on the filesystem revealed over 300 users, netcraft reported 280-something sites being hosted on the ip so it is a fair bet that over 300 sites were being hosted on it. Regardless of the hardware disk i/o is going oto be a serious issue on something hosting that many different sites.
@wazdog:
I think he meant the typo was "Christ", not the overselling of servers…
:oops:
pwahahaha… I didn't see that one. That is terribly funny, now just to decide if it is merited. I'm 40/60 heh.
Thanks wazdog for helping me out there
So I asume we are talking about the same company.
I also had to think alot if I choose Linode or that one.
Virtuozzo in fact has a great performence. I dont think that UML can beat that even when they try to compensate with fewer customers per server.
The big disadventage with the Virtuozzo host is that you are stuck with an old 7.1 RedHeat dispro (you can not switch to any other dispro like you can at Linode).