Can the Performance of one VPS Node being affected by other VPS Node?

Question

I am thinking about getting a VPS node from a hosting provider. But I am very unclear as to how the VPS node really works.

1. Assuming that the hosting provider promises Dedicated CPU of 2Ghz, 2 CPU Cores, Dedicated RAM 1000MB, does it follow that I will always get it, assuming that the hosting provider is not cheating me?
2. The VPS node can be a virtual machine, am I right?
3. In the event that it is a VM, and it cohabitats with a lot of other VMs on a server, will the usages of other VMs affect mine's performance?
4. Let's say in order to earn money, the hosting provider put too many VMs on a server, resulting in oversubscription ( assuming that for a server, the normal number of VMs can be put on it is 10, but the hosting provider puts 30), will that seriously impact my VM's performance?
5. How to ensure that the hosting provider won't oversubscribe?

Answer 1

1. Yes.

2. Yes.

3. Yes.

4. Yes.

5. Pick a reputable provider and if you are unsatisfied, change providers.

If the provider is reputable, your VPS should get an acceptable level of service, what you paid for, no matter what their other clients are doing.

One other thing -- CPU and RAM are important, but disk I/O is important too. While you may pay for dedicated cores and dedicated RAM, you don't usually get dedicated physical disks, and I/O usage of other VMs can shrink the system's disk cache, causing your disk I/Os to contend with everyone else's. Different providers handle this very differently.

Answer 2

Despite what I have written below; There are too many "IFs", "BUTs", "ANDs", "ORs" here for anyone to give you a correct answer except your hosting provider. You should be asking them these questions.

does it follow that I will always get it, assuming that the hosting provider is not cheating me?

How would you ever know for sure?

The VPS node can be a virtual machine, am I right?

Not "can", but "is". It is a virtual server.

In the event that it is a VM, and it cohabitats with a lot of other VMs on a server, will the usages of other VMs affect mine's performance?

That depends on the hosting provider: You need to check the SLA and T&Cs (small print) for their legal obligations and service agreements, it also depends on if the hosting provider over subscribes their physical infrastructure, or has any bottlenecks in their hosting infrastructure, and on the type of hosting and scheduling software being used.

Let's say in order to earn money, the hosting provider put too many VMs on a server, resulting in oversubscription ( assuming that for a server, the normal number of VMs can be put on it is 10, but the hosting provider puts 30), will that seriously impact my VM's performance?

This is a completely ambiguous question: How long is a piece of string? Who can tell how many other VMs will be on the same host as you, what they will all be doing, when they will be doing it, and how powerful the host machine will be? Only the hosting company.

How to ensure that the hosting provider won't oversubscribe

The only person(s) that can do that: The hosting company.