Re: [Xen-users] Not good performance on Xen

[Berillions <berillions@xxxxxxxxx>]

Hi Kun,

I have this error when i launch your command for 4 Dom0's VCPU (0-3) :

babaorheum@debian-desktop:~/Bureau$ sudo xl vcpu-pin 0 all 0-3 0-3
libxl: error: libxl.c:4970:libxl__set_vcpuaffinity: setting vcpu affinity: Invalid argument
libxl: warning: libxl.c:5033:libxl_set_vcpuaffinity_all: failed to set affinity for 0
libxl: error: libxl.c:4970:libxl__set_vcpuaffinity: setting vcpu affinity: Invalid argument
libxl: warning: libxl.c:5033:libxl_set_vcpuaffinity_all: failed to set affinity for 1
libxl: error: libxl.c:4970:libxl__set_vcpuaffinity: setting vcpu affinity: Invalid argument
libxl: warning: libxl.c:5033:libxl_set_vcpuaffinity_all: failed to set affinity for 2
libxl: error: libxl.c:4970:libxl__set_vcpuaffinity: setting vcpu affinity: Invalid argument
libxl: warning: libxl.c:5033:libxl_set_vcpuaffinity_all: failed to set affinity for 3
Could not set affinity.

2017-10-27 4:48 GMT+02:00 Kun Cheng <chengkunck@xxxxxxxxx>:

2017-10-27 2:52 GMT+08:00 Berillions <berillions@xxxxxxxxx>:
> Hello guys :-) ,
>
> Sorry for the delay, i was a little busy.
>
> @Kun Cheng :
> I did your suggestion but i don't know how to correctly use "xl vcpu-pin"
> with this configuration. If i don't use this command and launch the
> benchmark, the slowdown is less important but still exist and about the
> missing texture, this issue is gone.

Glad to hear it provided some help.

Now you have pinned the VCPUs of the guest to core 6-15 and limit Dom0 to
use 6 VCPUs, right? Because from your test data I saw 16 VCPUs for
dom0.

Could you try pin dom0's vcpus after entering Dom0 with cmds (root
privilege maybe required):

xl vcpu-pin 0 all 0-5 0-5

(change the number and range accordingly if you Dom0's VCPU
configuration is other than 6)

It sets Dom0's all(i.e. 6) VCPUs to core 0-5 with both hard and soft
CPU affinity (which means those VCPUs won't be migrated to other cores
during load balancing).

You could do the same to your guest VM if you wish. Remember don't let
your guest VM use core 0-5 in this case.

Maybe you can append -f to that cmd.

>
> @Dario Faggioli
> I did your test (during the benchmark) like you asked me and i share your my
> result for the test with 8 and 16 vcpus. I use pastebin, it's more clearly.
> - 8 cpus test : https://pastebin.com/JK48QRGz
> - 16 cous test : https://pastebin.com/FFiRBCYW
>
> Cheers,
> Maxime

_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxx
https://lists.xen.org/xen-users