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Diffstat (limited to 'Documentation/virt/kvm/halt-polling.rst')
| -rw-r--r-- | Documentation/virt/kvm/halt-polling.rst | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/Documentation/virt/kvm/halt-polling.rst b/Documentation/virt/kvm/halt-polling.rst index 3fae39b1a5ba..4f1a1b23d99c 100644 --- a/Documentation/virt/kvm/halt-polling.rst +++ b/Documentation/virt/kvm/halt-polling.rst @@ -112,11 +112,11 @@ powerpc kvm-hv case. | | function. | | +-----------------------+---------------------------+-------------------------+ -These module parameters can be set from the debugfs files in: +These module parameters can be set from the sysfs files in: /sys/module/kvm/parameters/ -Note: that these module parameters are system wide values and are not able to +Note: these module parameters are system-wide values and are not able to be tuned on a per vm basis. Any changes to these parameters will be picked up by new and existing vCPUs the @@ -142,12 +142,12 @@ Further Notes global max polling interval (halt_poll_ns) then the host will always poll for the entire block time and thus cpu utilisation will go to 100%. -- Halt polling essentially presents a trade off between power usage and latency and +- Halt polling essentially presents a trade-off between power usage and latency and the module parameters should be used to tune the affinity for this. Idle cpu time is essentially converted to host kernel time with the aim of decreasing latency when entering the guest. - Halt polling will only be conducted by the host when no other tasks are runnable on that cpu, otherwise the polling will cease immediately and schedule will be invoked to - allow that other task to run. Thus this doesn't allow a guest to denial of service the - cpu. + allow that other task to run. Thus this doesn't allow a guest to cause denial of service + of the cpu. |