// try to add a replica, return success or not
func (self *Block) AddReplica(loc proc.ServerLocation) bool {
index := self.findIndex(loc)
if index != -1 {
// not add but return true
return true
}
if len(self.block.Locations) >= config.ReplicaCount() {
// will not add
return false
}
self.block.Locations = append(self.block.Locations, loc)
return true
}
// compute the location for a new block
func (self *SlaveManager) NewBlockReplica() []proc.ServerLocation {
h := &SlaveHeap{}
heap.Init(h)
for _, slave := range self.slaves {
heap.Push(h, slave)
}
var locations []proc.ServerLocation
for h.Len() > 0 && len(locations) < config.ReplicaCount() {
slave := heap.Pop(h).(*Slave)
if slave.IsAlive(time.Now()) {
locations = append(locations, slave.Location())
}
}
return locations
}