Which CPU instruction are recommend for virtualization?

[Henning Blanke _Communardo_]

In virtualized environments, it is possible that CPU instruction set limit. In my opinion, the performance may have problems.
Which CPU instruction should necessarily be available to ensure a high-performance operation?
Is there any experience? What Instruction are activated at Atlassian Cloud? Or maybe even disabled?

[rrudnicki]

Hi Henning, 

I know that sometimes scale environments are complicated. However, bear in mind that it isn't only CPU you should concern about when thinking about performance. It will depend on many different factors, for example:

# The number of concurrent users that you will have;

# If your application will have a huge coefficient of Read/Write;

# If you will run it over SSL or not;

# How many other virtual machines will be running over its hypervisor (it could affect some I/O), etc... 

To sum up, unfortunately, Atlassian doesn't have a complete documentation about the virtualized environments yet, because as I said, it depends on many different factors. 

However, you can check this link about Confluence running in virtualized environments and this one about hardware requirements for Confluence.

Also, if you need some especial assistance to set your environment up, you might want to contact an Atlassian Expert.

What I could recommend you to do, based on my previous experiences, is:

•  Create a test environment following the hardware requirements documentation.
• Try to predict how this system will grow: disk space, users, concurrent requests in the next two
  years, etc. With this information, you will be able to have an idea of how much of CPU and memory you'll need, what kind of disk, space in disk, throughput, etc. 

• Do some load tests using JMETER.

Hope it helps.

Renato Rudnicki