CPU usage on VPS

[DeNasio]

Hello,

A week ago I was on a shared server. Then suddenly the traffic on my site started to increase. I was told that my scripts were using too much CPU and that I was affecting my neighbors on the shared server. My scripts were disabled and I was advised to move to a semi-dedicated server.

My traffic kept increasing. Again I was told that my scripts were using too much CPU and that I was affecting my neighbors on the semi-dedicated server. My scripts were disabled again and I was advised to move to a dedicated server.

Now I'm on a VPS. Am I right to assume that I will be the only one who will be affected if my scripts are using too many CPU on the VPS? So no more disabling my scripts because I'm affecting my neighbors?

[JPC-Masood]

No, if you upgraded from shared to sdx for the CPU usage, you should have moved to Dedicated Server. CPU is still shared in VPS environment and it may cause problems for other users on your node.

[DeNasio]

No, if you upgraded from shared to sdx for the CPU usage, you should have moved to Dedicated Server. CPU is still shared in VPS environment and it may cause problems for other users on your node.

What you are saying contradicts with what Greg is saying in the following post:

http://www.jaguarpc.com/forums/showthread.php?t=15978

Each VPS is completely independent for eachother. If one VPS on the server is being attacked (by a DoS for instance) all the other VPS's are completely unaffected since they have their guaranteed (dedicated) amount of resources. VPS's cannot affect eachother in any way. In nearly every perspective you can see a VPS as if it's a dedicated server.

So if the VPS are completely independent from each other, how can my CPU usage affect the others? All VPS has their guaranteed (dedicated) amount of resources?

What you are saying also contradicts with what Greg said in a post on WebhostingTalk.com:

http://www.webhostingtalk.com/showpo...7&postcount=10

If you load down your vps the only one complaining would be you the owner.

[Ron]

What kind of traffic are you seeing, and what kind of software do you have running? Is the CPU usage problem in MySQL or in PHP or something else? Have you tried to optimize your software?

You can throw hardware at perfomance issue until you go broke. Now that you're on a VPS you can install all sorts of performance monitors and find your problem.

[DeNasio]

What kind of traffic are you seeing, and what kind of software do you have running? Is the CPU usage problem in MySQL or in PHP or something else? Have you tried to optimize your software?

You can throw hardware at perfomance issue until you go broke. Now that you're on a VPS you can install all sorts of performance monitors and find your problem.

You are right, I intend to look into my CPU usage. But first I would like to know what the chances are that my scripts would be disabled on my VPS server because I'm "affecting my neighbors". This already happened twice in the last week and I don't want it to happen again. It is not good for business!

[thisisit3]

Nobody can tell you that for sure. We've seen posts by another member who had issues with his VPS and support told him that another VPS on the server was affecting him. So it seems a VPS can still affect others.

ofcourse your kilometers may vary

[DeNasio]

Nobody can tell you that for sure. We've seen posts by another member who had issues with his VPS and support told him that another VPS on the server was affecting him. So it seems a VPS can still affect others.

ofcourse your kilometers may vary

So what Greg says in his posts are bull?

[Ron]

I think the correct phrase might be "It's a complicated issue"

[JPC-Masood]

What you are saying contradicts with what Greg is saying

I have pointed Greg to this thread.

Virtuozzo is a fair share CPU environment. There is no CPU isolation. Ref: http://www.swsoft.com/en/products/virtuozzo/os/

This actually comes as an advantage and IMHO and experience has a lot more efficiency as compared to the hypervisor model.

[JPC-Greg]

You can set cpu limits on vps nodes for each vps. We started out that way but I was just reminded that we changed to "equal share" not too long ago . Apparantly that method affords everyone better performance and has become an industry standard that helped alleviate some complaints widestream vps users had.

[Gwaihir]

Virtuozzo is a fair share CPU environment. There is no CPU isolation. Ref: http://www.swsoft.com/en/products/virtuozzo/os/

This actually comes as an advantage and IMHO and experience has a lot more efficiency as compared to the hypervisor model.

Virtuozzo definately offers a lot more effenciency than emulating hardware and placing separate OSses in each virtual environment. However, I'm missing the link with this topic completely; it doesn't mention the CPU allocation options there, nor the up / downsides of each choice (fair share or otherwise). Pity; this fair share 'solution' clearly has downsides that undermine the nature of the VPS (not being overly affected by others on the server or being able to overly affect them). Would be nice to get some info on how much worse 'the other way' is.

[DeNasio]

So now I'll have to just sit and wait till my scripts get disabled again for affecting my neighbors on the VPS server huh?

[Ron]

Instead of sitting and waiting, find your resource hog(s) and fix it(them), then go back to shared!

[DeNasio]

Instead of sitting and waiting, find your resource hog(s) and fix it(them), then go back to shared!

This is what I intend to do. But this process takes time. And afraid that JaguarPC will start complaining soon about my scripts affecting my neighbors. If I knew that my scripts can't affect my neighbors, then I will take the time to find the resources hogs and fix them!

[Ron]

I know that sometimes things take time to find, but you must already have an idea of what pages are getting hit and what seems like it's taking a lot of CPU? How many visitors/pageviews are you getting a day?

From all that has been said, I'd be looking for the problems sooner rather than later! Apply the 80-20 rule and fix the things that give big bang for the buck first.

If you need another pair of eyes, drop me a PM and I'll see if I can help.