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
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
|
package topology
import (
"code.google.com/p/weed-fs/go/storage"
"errors"
"log"
"math/rand"
)
type VolumeLayout struct {
repType storage.ReplicationType
vid2location map[storage.VolumeId]*VolumeLocationList
writables []storage.VolumeId // transient array of writable volume id
pulse int64
volumeSizeLimit uint64
}
func NewVolumeLayout(repType storage.ReplicationType, volumeSizeLimit uint64, pulse int64) *VolumeLayout {
return &VolumeLayout{
repType: repType,
vid2location: make(map[storage.VolumeId]*VolumeLocationList),
writables: *new([]storage.VolumeId),
pulse: pulse,
volumeSizeLimit: volumeSizeLimit,
}
}
func (vl *VolumeLayout) RegisterVolume(v *storage.VolumeInfo, dn *DataNode) {
if _, ok := vl.vid2location[v.Id]; !ok {
vl.vid2location[v.Id] = NewVolumeLocationList()
}
if vl.vid2location[v.Id].Add(dn) {
if len(vl.vid2location[v.Id].list) == v.RepType.GetCopyCount() {
if vl.isWritable(v) {
vl.writables = append(vl.writables, v.Id)
}
}
}
}
func (vl *VolumeLayout) isWritable(v *storage.VolumeInfo) bool {
return uint64(v.Size) < vl.volumeSizeLimit &&
v.Version == storage.CurrentVersion &&
!v.ReadOnly
}
func (vl *VolumeLayout) Lookup(vid storage.VolumeId) []*DataNode {
if location := vl.vid2location[vid]; location != nil {
return location.list
}
return nil
}
func (vl *VolumeLayout) PickForWrite(count int, dataCenter string) (*storage.VolumeId, int, *VolumeLocationList, error) {
len_writers := len(vl.writables)
if len_writers <= 0 {
log.Println("No more writable volumes!")
return nil, 0, nil, errors.New("No more writable volumes!")
}
if dataCenter == "" {
vid := vl.writables[rand.Intn(len_writers)]
locationList := vl.vid2location[vid]
if locationList != nil {
return &vid, count, locationList, nil
}
return nil, 0, nil, errors.New("Strangely vid " + vid.String() + " is on no machine!")
} else {
var vid storage.VolumeId
var locationList *VolumeLocationList
counter := 0
for _, v := range vl.writables {
volumeLocationList := vl.vid2location[v]
for _, dn := range volumeLocationList.list {
if dn.GetDataCenter().Id() == NodeId(dataCenter) {
counter++
if rand.Intn(counter) < 1 {
vid, locationList = v, volumeLocationList
}
}
}
}
return &vid, count, locationList, nil
}
return nil, 0, nil, errors.New("Strangely This Should Never Have Happened!")
}
func (vl *VolumeLayout) GetActiveVolumeCount(dataCenter string) int {
if dataCenter == "" {
return len(vl.writables)
}
counter := 0
for _, v := range vl.writables {
for _, dn := range vl.vid2location[v].list {
if dn.GetDataCenter().Id() == NodeId(dataCenter) {
counter++
}
}
}
return counter
}
func (vl *VolumeLayout) removeFromWritable(vid storage.VolumeId) bool {
for i, v := range vl.writables {
if v == vid {
log.Println("Volume", vid, "becomes unwritable")
vl.writables = append(vl.writables[:i], vl.writables[i+1:]...)
return true
}
}
return false
}
func (vl *VolumeLayout) setVolumeWritable(vid storage.VolumeId) bool {
for _, v := range vl.writables {
if v == vid {
return false
}
}
log.Println("Volume", vid, "becomes writable")
vl.writables = append(vl.writables, vid)
return true
}
func (vl *VolumeLayout) SetVolumeUnavailable(dn *DataNode, vid storage.VolumeId) bool {
if vl.vid2location[vid].Remove(dn) {
if vl.vid2location[vid].Length() < vl.repType.GetCopyCount() {
log.Println("Volume", vid, "has", vl.vid2location[vid].Length(), "replica, less than required", vl.repType.GetCopyCount())
return vl.removeFromWritable(vid)
}
}
return false
}
func (vl *VolumeLayout) SetVolumeAvailable(dn *DataNode, vid storage.VolumeId) bool {
if vl.vid2location[vid].Add(dn) {
if vl.vid2location[vid].Length() >= vl.repType.GetCopyCount() {
return vl.setVolumeWritable(vid)
}
}
return false
}
func (vl *VolumeLayout) SetVolumeCapacityFull(vid storage.VolumeId) bool {
return vl.removeFromWritable(vid)
}
func (vl *VolumeLayout) ToMap() interface{} {
m := make(map[string]interface{})
m["replication"] = vl.repType.String()
m["writables"] = vl.writables
//m["locations"] = vl.vid2location
return m
}
|
