On Wed, Jun 29, 2022 at 5:43 AM Stephen Morris <samorris@netsace.net.au> wrote:
On 22/6/22 23:54, Matthew Miller wrote:
> [...]
> Or, `cpu-x` for a GUI view with a lot of detail.
Thanks Greg. I installed cpu-x and tried all the commands. What makes
the first two processes difficult from my perspective is the cpu I have
has 32 treads all of which are the same so the first two processes lists
all 32.
I ran the cpu-x bench marks for random numbers and what was interesting
was the results for 32 threads were only around 16 times the result for
1 thread, which is probably to be expected given the cpu has 16 cores.

My experience was that disabling hyperthreading didn't reduce throughput.
These multi-core systems generally do better with integer workloads, I think some
have one f.p. unit per core.   There can be very counterintuitive performance
changes due to CPU cache issues and communications overhead.  My experience
is mostly with I/O intensive workloads.  We generally found it best to limit those tasks
to a fraction of the cores so background tasks (job control/monitoring, backups, etc)
didn't stall.  After a big effort to make efficient use of all the cores you may
encounter thermal throttling.   It was better to adjust the workload to avoid
thermal issues: more consistent thruput and fewer issues with background tasks.

 
--
George N. White III