/
dmap_eviction.go
100 lines (93 loc) · 2.19 KB
/
dmap_eviction.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
88
89
90
91
92
93
94
95
96
97
98
99
100
// Copyright 2018 Burak Sezer
//
// 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,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package olricdb
import (
"math/rand"
"sync"
"time"
)
func (db *OlricDB) evictKeysAtBackground() {
defer db.wg.Done()
ticker := time.NewTicker(time.Second)
defer ticker.Stop()
for {
select {
case <-db.ctx.Done():
return
case <-ticker.C:
db.evictKeys()
}
}
}
func (db *OlricDB) evictKeys() {
partID := uint64(rand.Intn(int(db.config.PartitionCount)))
part := db.partitions[partID]
part.RLock()
var wg sync.WaitGroup
dcount := 0
for name, dm := range part.m {
dcount++
if dcount >= 20 {
break
}
wg.Add(1)
go db.scanDMapForEviction(partID, name, dm, &wg)
}
part.RUnlock()
wg.Wait()
}
func (db *OlricDB) scanDMapForEviction(partID uint64, name string, dm *dmap, wg *sync.WaitGroup) {
/*
1- Test 20 random keys from the set of keys with an associated expire.
2- Delete all the keys found expired.
3- If more than 25% of keys were expired, start again from step 1.
*/
defer wg.Done()
dm.Lock()
defer dm.Unlock()
var totalCount = 0
var maxKcount = 20
janitor := func() bool {
dcount, kcount := 0, 0
for hkey, vdata := range dm.d {
kcount++
if kcount >= maxKcount {
break
}
if isKeyExpired(vdata.TTL) {
err := db.delKeyVal(dm, hkey, name)
if err != nil {
db.logger.Printf("[ERROR] Failed to delete expired hkey: %d on DMap: %s: %v", hkey, name, err)
continue
}
dcount++
}
}
totalCount += dcount
return dcount >= maxKcount/4
}
defer func() {
db.logger.Printf("[DEBUG] Evicted key count is %d on PartID: %d", totalCount, partID)
}()
for {
select {
case <-db.ctx.Done():
return
default:
}
if !janitor() {
return
}
}
}