Re: NetBSD/Xen samba performance low (compared to NetBSD/amd64)

[Sad Clouds <cryintothebluesky%gmail.com@localhost>]

On Mon, 3 Aug 2020 15:08:28 +0200
Matthias Petermann <mp%petermann-it.de@localhost> wrote:

> I measured this by copying an 8 GB ISO file from a Windows host.
> In constellation 2, no guests had started and the full main memory of 
> Dom0 was assigned. In my view, the only significant difference is
> that NetBSD can only use one of the two CPU cores under Xen. Since
> the CPU was idle on average at 20% during copying, that doesn't seem
> to be the bottleneck?

I believe Samba is single threaded, so can't take advantage of multiple
CPUs for a single stream. I'm not a Xen expert, however I'm not sure
running this in Dom0 is a representative test. I imagine most workloads
would be done within a DomU, while Dom0 is just a control domain and
allocates CPU and memory resources, so you may have additional
overheads + latencies.

Best to start testing simple use-cases, i.e. simple disk I/O with dd, or
network I/O with iperf, and narrow down the issue.