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very slow cpu for compute instances on TripleO in virtual environment

Hello,

I have a TripleoO setup in virtual environment. 1 controller 1 compute 1 ceph

If I run the following command on the compute node itself:

sysbench --test=cpu --cpu-max-prime=10000 --num-threads=1 run

it gives:

Test execution summary: total time: 10.4219s total number of events: 10000 total time taken by event execution: 10.4205 per-request statistics: min: 0.98ms avg: 1.04ms max: 1.36ms approx. 95 percentile: 1.13ms

Spawning an instance with 2 vCPUs, 4 Gb RAM and running the same command, the result is:

Test execution summary:
    total time:                          44.2215s
    total number of events:              10000
    total time taken by event execution: 44.1548
    per-request statistics:
         min:                                  3.51ms
         avg:                                  4.42ms
         max:                                 17.90ms
         approx.  95 percentile:               4.73ms

Threads fairness:
    events (avg/stddev):           10000.0000/0.00
    execution time (avg/stddev):   44.1548/0.00

So more than 4 times slower. I believe the reason is that qemu is used instead of kvm for instances virtualization.

The TripleO installation specifies that nested KVM is not supported:

http://docs.openstack.org/developer/tripleo-docs/environments/environments.html Virtualization hardware extensions enabled (nested KVM is not supported)

Is there any way to use nested kvm with TripleO. If not, what could I do in terms of configuration in order to increase the qemu's performance ?

Thanks.

very slow cpu for compute instances on TripleO in virtual environment

Hello,

I have a TripleoO setup in virtual environment. 1 controller 1 compute 1 ceph

If I run the following command on the compute node itself:

sysbench --test=cpu --cpu-max-prime=10000 --num-threads=1 run

it gives:

Test execution summary:
    total time:                          10.4219s
    total number of events:              10000
    total time taken by event execution: 10.4205
    per-request statistics:
         min:                                  0.98ms
         avg:                                  1.04ms
         max:                                  1.36ms
         approx.  95 percentile:               1.13ms

1.13ms

Spawning an instance with 2 vCPUs, 4 Gb RAM and running the same command, the result is:

Test execution summary:
    total time:                          44.2215s
    total number of events:              10000
    total time taken by event execution: 44.1548
    per-request statistics:
         min:                                  3.51ms
         avg:                                  4.42ms
         max:                                 17.90ms
         approx.  95 percentile:               4.73ms

Threads fairness:
    events (avg/stddev):           10000.0000/0.00
    execution time (avg/stddev):   44.1548/0.00

So more than 4 times slower. I believe the reason is that qemu is used instead of kvm for instances virtualization.

The TripleO installation specifies that nested KVM is not supported:

http://docs.openstack.org/developer/tripleo-docs/environments/environments.html Virtualization hardware extensions enabled (nested KVM is not supported)

Is there any way to use nested kvm with TripleO. If not, what could I do in terms of configuration in order to increase the qemu's performance ?

Thanks.

very slow cpu for compute instances on TripleO in virtual environment

Hello,

I have a TripleoO setup in virtual environment. 1 controller 1 compute 1 ceph

If I run the following command on the compute node itself:

sysbench --test=cpu --cpu-max-prime=10000 --num-threads=1 run

it gives:

Test execution summary:
    total time:                          10.4219s
    total number of events:              10000
    total time taken by event execution: 10.4205
    per-request statistics:
         min:                                  0.98ms
         avg:                                  1.04ms
         max:                                  1.36ms
         approx.  95 percentile:               1.13ms

Spawning an instance with 2 vCPUs, 4 Gb RAM and running the same command, the result is:

Test execution summary:
    total time:                          44.2215s
    total number of events:              10000
    total time taken by event execution: 44.1548
    per-request statistics:
         min:                                  3.51ms
         avg:                                  4.42ms
         max:                                 17.90ms
         approx.  95 percentile:               4.73ms

Threads fairness:
    events (avg/stddev):           10000.0000/0.00
    execution time (avg/stddev):   44.1548/0.00

So more than 4 times slower. I believe the reason is that qemu is used instead of kvm for instances virtualization.

The TripleO installation specifies that nested KVM is not supported:

http://docs.openstack.org/developer/tripleo-docs/environments/environments.html Virtualization hardware extensions enabled (nested KVM is not supported)

Is there any way to use nested kvm with TripleO. If not, what could I do in terms of configuration in order to increase the qemu's performance ?

Thanks.