Re: Question: t/io_uring performance

[Erwan Velu <e.velu@criteo.com>]

Le 08/09/2021 à 19:11, Erwan Velu a écrit :
> [..]
> Enabling 32 poll queues:
> [...]
>
> 2 devices, 2 thread nostats : taskset -c 0,1 t/io_uring -b512 -d128 
> -c32 -s32 -p1 -F1 -B1 -n2 /dev/nvme2n1 /dev/nvme3n1 : 1.84M


Just realized something here, i'm using 2 devices with 2 cores for a 
good 1.84M, but cores 0 and 1 are not on the same physical core.

But I could also use 2 logical cores but this time located on the same 
physical core.

Thanks to the good Zen2 hyper-threading, this should give me nice numbers.


So I made a try !


2 devices on a single physical core brings me up to 1.23M (that's 67% of 
the previous result on two physical cores)

3 devices on a two physical cores bring me up to 1.85M

4 devices on a two physical cores bring me up to 2.48M

4 devices on a three physical cores bring me up to 3.77M


That's really great numbers ...