[ovirt-users] Re: Best performance for vcpu pinning
Hi Klaas,
in our case, the Hypervisor CPU looks like this:
CPU(s): 32
On-line CPU(s) list: 0-31
Thread(s) per core: 2
Core(s) per socket: 8
Socket(s): 2
NUMA node(s): 2
NUMA node0 CPU(s): 0-7,16-23
NUMA node1 CPU(s): 8-15,24-31
The PROD VM should have 24 PINNED (due to licensing requirements) vCPUs out of the 32
threads and around 838G of the 1 TB RAM.
The TEST VM should have 8 vCPUs out of the 32 threads and around 128G of 1 TB RAM.
With these PROD VM Requirements, it does not make sense to limit vCPUs to one socket /
NUMA node. The TEST VM can be limited to one socket.
I guess I have made these mistakes:
- I should not use Physical CPU thread 0 but leave it for Hypervisor
- I have configured the VM "2 threads per core" with <topology
sockets='16' cores='6' threads='2'/>, but have not specified
two threads for each vCPU in the pinning field. In the oVirt "Resource
Allocation" Tab in "CPU Pinning Topology", i have specified:
0#8_1#9_2#10_3#11_4#12_5#13_6#14_7#15_8#16_9#17_10#18_11#19_12#20_13#21_14#22_15#23_16#24_17#25_18#26_19#27_20#28_21#29_22#30_23#31
The Calculate CPU Pinning script from the RHV HANA Guide results in this mapping:
0#1,17
1#1,17
2#2,18
3#2,18
4#3,19
5#3,19
6#4,20
7#4,20
8#5,21
9#5,21
10#6,22
11#6,22
12#9,25
13#9,25
14#10,26
15#10,26
16#11,27
17#11,27
18#12,28
19#12,28
20#13,29
21#13,29
22#14,30
23#14,30
But with this approach, I can not separate CPUs between PROD VM and TEST VM.
Any ideas?