// qos compares pods by QoS (BestEffort < Burstable < Guaranteed)
func qosComparator(p1, p2 *api.Pod) int {
qosP1 := qos.GetPodQos(p1)
qosP2 := qos.GetPodQos(p2)
// its a tie
if qosP1 == qosP2 {
return 0
}
// if p1 is best effort, we know p2 is burstable or guaranteed
if qosP1 == qos.BestEffort {
return -1
}
// we know p1 and p2 are not besteffort, so if p1 is burstable, p2 must be guaranteed
if qosP1 == qos.Burstable {
if qosP2 == qos.Guaranteed {
return -1
}
return 1
}
// ok, p1 must be guaranteed.
return 1
}
// Admit rejects a pod if its not safe to admit for node stability.
func (m *managerImpl) Admit(attrs *lifecycle.PodAdmitAttributes) lifecycle.PodAdmitResult {
m.RLock()
defer m.RUnlock()
if len(m.nodeConditions) == 0 {
return lifecycle.PodAdmitResult{Admit: true}
}
notBestEffort := qos.BestEffort != qos.GetPodQos(attrs.Pod)
if notBestEffort {
return lifecycle.PodAdmitResult{Admit: true}
}
glog.Warningf("Failed to admit pod %v - %s", format.Pod(attrs.Pod), "node has conditions: %v", m.nodeConditions)
// we reject all best effort pods until we are stable.
return lifecycle.PodAdmitResult{
Admit: false,
Reason: reason,
Message: message,
}
}
// Determine if a pod is scheduled with best-effort QoS
func isPodBestEffort(pod *api.Pod) bool {
return qos.GetPodQos(pod) == qos.BestEffort
}