docs/strategy/binpacking.go

82 lines
1.5 KiB
Go

package strategy
import (
"errors"
"sort"
"github.com/docker/swarm/cluster"
"github.com/samalba/dockerclient"
)
var (
ErrNoResourcesAvailable = errors.New("no resources available to schedule container")
)
type BinPackingPlacementStrategy struct{}
func (p *BinPackingPlacementStrategy) Initialize() error {
return nil
}
func (p *BinPackingPlacementStrategy) PlaceContainer(config *dockerclient.ContainerConfig, nodes []*cluster.Node) (*cluster.Node, error) {
scores := scores{}
for _, node := range nodes {
nodeMemory := node.UsableMemory()
nodeCpus := node.UsableCpus()
// Skip nodes that are smaller than the requested resources.
if nodeMemory < int64(config.Memory) || nodeCpus < config.CpuShares {
continue
}
var (
cpuScore int64 = 100
memoryScore int64 = 100
)
if config.CpuShares > 0 {
cpuScore = (node.ReservedCpus() + config.CpuShares) * 100 / nodeCpus
}
if config.Memory > 0 {
memoryScore = (node.ReservedMemory() + config.Memory) * 100 / nodeMemory
}
if cpuScore <= 100 && memoryScore <= 100 {
scores = append(scores, &score{node: node, score: cpuScore + memoryScore})
}
}
if len(scores) == 0 {
return nil, ErrNoResourcesAvailable
}
sort.Sort(scores)
return scores[0].node, nil
}
type score struct {
node *cluster.Node
score int64
}
type scores []*score
func (s scores) Len() int {
return len(s)
}
func (s scores) Swap(i, j int) {
s[i], s[j] = s[j], s[i]
}
func (s scores) Less(i, j int) bool {
var (
ip = s[i]
jp = s[j]
)
return ip.score > jp.score
}