Poor memory allocation performance with a lot of threads on 36 core machine

[Bottled Gin via Digitalmars-d]

On Thursday, 18 February 2016 at 13:00:12 UTC, Witek wrote:

> Anyhow, everything was good on 1 or 2 threads, or maybe few 
> more, on my laptop with old Dual Core CPU. I was able to speed 
> it up exactly by a factor of 2x.
>
> I wanted to try it out on bigger machine, so used Amazone AWS 
> EC2 c4.8xlarge instance with 18 cores, 36 hyperthreads/vCPUs, 
> and results were pretty terrible.

In my experience multicore on a VPS does not work the same way as 
muticore on a local dedicated machine. But my experience is from 
a Linode instance back in 2014 when Linode only offered XEN 
virtualization. It will be interesting to see how a Linode pans 
out now that they offer KVM. I would encourage you to try with a 
2-core Amazon AWS and see if you get a 2X performance scaling as 
you got with a dedicated machine.

- Puneet