forked from tikv/pd
-
Notifications
You must be signed in to change notification settings - Fork 1
/
random_merge.go
87 lines (74 loc) · 2.62 KB
/
random_merge.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
// Copyright 2018 PingCAP, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// See the License for the specific language governing permissions and
// limitations under the License.
package schedulers
import (
"math/rand"
"github.com/pingcap/pd/server/core"
"github.com/pingcap/pd/server/schedule"
)
func init() {
schedule.RegisterScheduler("random-merge", func(limiter *schedule.Limiter, args []string) (schedule.Scheduler, error) {
return newRandomMergeScheduler(limiter), nil
})
}
type randomMergeScheduler struct {
*baseScheduler
selector *schedule.RandomSelector
}
// newRandomMergeScheduler creates an admin scheduler that shuffles regions
// between stores.
func newRandomMergeScheduler(limiter *schedule.Limiter) schedule.Scheduler {
filters := []schedule.Filter{schedule.StoreStateFilter{MoveRegion: true}}
base := newBaseScheduler(limiter)
return &randomMergeScheduler{
baseScheduler: base,
selector: schedule.NewRandomSelector(filters),
}
}
func (s *randomMergeScheduler) GetName() string {
return "random-merge-scheduler"
}
func (s *randomMergeScheduler) GetType() string {
return "random-merge"
}
func (s *randomMergeScheduler) IsScheduleAllowed(cluster schedule.Cluster) bool {
return s.limiter.OperatorCount(schedule.OpMerge) < cluster.GetMergeScheduleLimit()
}
func (s *randomMergeScheduler) Schedule(cluster schedule.Cluster, opInfluence schedule.OpInfluence) []*schedule.Operator {
schedulerCounter.WithLabelValues(s.GetName(), "schedule").Inc()
stores := cluster.GetStores()
store := s.selector.SelectSource(cluster, stores)
if store == nil {
schedulerCounter.WithLabelValues(s.GetName(), "no_store").Inc()
return nil
}
region := cluster.RandLeaderRegion(store.GetId(), core.HealthRegion())
if region == nil {
schedulerCounter.WithLabelValues(s.GetName(), "no_region").Inc()
return nil
}
target, other := cluster.GetAdjacentRegions(region)
if (rand.Int()%2 == 0 && other != nil) || target == nil {
target = other
}
if target == nil {
schedulerCounter.WithLabelValues(s.GetName(), "no_adjacent").Inc()
return nil
}
schedulerCounter.WithLabelValues(s.GetName(), "new_operator").Inc()
op1, op2, err := schedule.CreateMergeRegionOperator("random-merge", cluster, region, target, schedule.OpAdmin)
if err != nil {
return nil
}
return []*schedule.Operator{op1, op2}
}