mirror of https://github.com/go-redis/redis.git
Merge pull request #1361 from go-redis/feature/rendezvous-hash
Use Rendezvous in Ring. Thanks @rafaeleyng for initial idea and implementation
This commit is contained in:
Vladimir Mihailenco
GitHub
commit
0f875ec0f6
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@ -0,0 +1,4 @@
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semi: false
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singleQuote: true
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proseWrap: always
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printWidth: 80
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63
CHANGELOG.md
63
CHANGELOG.md
|
|
@ -2,37 +2,63 @@
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|||
|
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## v8 (unreleased)
|
||||
|
||||
- All commands accept `context.Context` as first argument.
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- All commands require `context.Context` as a first argument, e.g.
|
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`rdb.Ping(ctx)`. If you are not using `context.Context` yet, the simplest
|
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option is to define package variable `var ctx = context.TODO()` and use it
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when `ctx` is expected.
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- Ring uses Rendezvous Hashing by default which provides better distribution.
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This means that existing keys must be moved to a new location or key will be
|
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inaccessible / lost. To use old hashing scheme:
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|
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```go
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import "github.com/golang/groupcache/consistenthash"
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ring := redis.NewRing(&redis.RingOptions{
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NewConsistentHash: func() {
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return consistenthash.New(100, crc32.ChecksumIEEE)
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},
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})
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```
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||||
|
||||
- Basic support for OpenTelemetry instrumentation.
|
||||
|
||||
## v7.3
|
||||
|
||||
- New option `Options.Username` which causes client to use `AuthACL`. Be aware if your connection URL contains username.
|
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- New option `Options.Username` which causes client to use `AuthACL`. Be aware
|
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if your connection URL contains username.
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|
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## v7.2
|
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|
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- Existing `HMSet` is renamed to `HSet` and old deprecated `HMSet` is restored for Redis 3 users.
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- Existing `HMSet` is renamed to `HSet` and old deprecated `HMSet` is restored
|
||||
for Redis 3 users.
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||||
|
||||
## v7.1
|
||||
|
||||
- Existing `Cmd.String` is renamed to `Cmd.Text`. New `Cmd.String` implements `fmt.Stringer` interface.
|
||||
- Existing `Cmd.String` is renamed to `Cmd.Text`. New `Cmd.String` implements
|
||||
`fmt.Stringer` interface.
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|
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## v7
|
||||
|
||||
- _Important_. Tx.Pipeline now returns a non-transactional pipeline. Use Tx.TxPipeline for a transactional pipeline.
|
||||
- WrapProcess is replaced with more convenient AddHook that has access to context.Context.
|
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- _Important_. Tx.Pipeline now returns a non-transactional pipeline. Use
|
||||
Tx.TxPipeline for a transactional pipeline.
|
||||
- WrapProcess is replaced with more convenient AddHook that has access to
|
||||
context.Context.
|
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- WithContext now can not be used to create a shallow copy of the client.
|
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- New methods ProcessContext, DoContext, and ExecContext.
|
||||
- Client respects Context.Deadline when setting net.Conn deadline.
|
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- Client listens on Context.Done while waiting for a connection from the pool and returns an error when context context is cancelled.
|
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- Add PubSub.ChannelWithSubscriptions that sends `*Subscription` in addition to `*Message` to allow detecting reconnections.
|
||||
- `time.Time` is now marshalled in RFC3339 format. `rdb.Get("foo").Time()` helper is added to parse the time.
|
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- Client listens on Context.Done while waiting for a connection from the pool
|
||||
and returns an error when context context is cancelled.
|
||||
- Add PubSub.ChannelWithSubscriptions that sends `*Subscription` in addition to
|
||||
`*Message` to allow detecting reconnections.
|
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- `time.Time` is now marshalled in RFC3339 format. `rdb.Get("foo").Time()`
|
||||
helper is added to parse the time.
|
||||
- `SetLimiter` is removed and added `Options.Limiter` instead.
|
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- `HMSet` is deprecated as of Redis v4.
|
||||
|
||||
## v6.15
|
||||
|
||||
- Cluster and Ring pipelines process commands for each node in its own goroutine.
|
||||
- Cluster and Ring pipelines process commands for each node in its own
|
||||
goroutine.
|
||||
|
||||
## 6.14
|
||||
|
||||
|
|
@ -40,16 +66,23 @@
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- Added Options.MaxConnAge.
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||||
- PoolStats.FreeConns is renamed to PoolStats.IdleConns.
|
||||
- Add Client.Do to simplify creating custom commands.
|
||||
- Add Cmd.String, Cmd.Int, Cmd.Int64, Cmd.Uint64, Cmd.Float64, and Cmd.Bool helpers.
|
||||
- Add Cmd.String, Cmd.Int, Cmd.Int64, Cmd.Uint64, Cmd.Float64, and Cmd.Bool
|
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helpers.
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- Lower memory usage.
|
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|
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## v6.13
|
||||
|
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- Ring got new options called `HashReplicas` and `Hash`. It is recommended to set `HashReplicas = 1000` for better keys distribution between shards.
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- Cluster client was optimized to use much less memory when reloading cluster state.
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- PubSub.ReceiveMessage is re-worked to not use ReceiveTimeout so it does not lose data when timeout occurres. In most cases it is recommended to use PubSub.Channel instead.
|
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- Ring got new options called `HashReplicas` and `Hash`. It is recommended to
|
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set `HashReplicas = 1000` for better keys distribution between shards.
|
||||
- Cluster client was optimized to use much less memory when reloading cluster
|
||||
state.
|
||||
- PubSub.ReceiveMessage is re-worked to not use ReceiveTimeout so it does not
|
||||
lose data when timeout occurres. In most cases it is recommended to use
|
||||
PubSub.Channel instead.
|
||||
- Dialer.KeepAlive is set to 5 minutes by default.
|
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|
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## v6.12
|
||||
|
||||
- ClusterClient got new option called `ClusterSlots` which allows to build cluster of normal Redis Servers that don't have cluster mode enabled. See https://godoc.org/github.com/go-redis/redis#example-NewClusterClient--ManualSetup
|
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- ClusterClient got new option called `ClusterSlots` which allows to build
|
||||
cluster of normal Redis Servers that don't have cluster mode enabled. See
|
||||
https://godoc.org/github.com/go-redis/redis#example-NewClusterClient--ManualSetup
|
||||
|
|
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|||
2
go.mod
2
go.mod
|
|
@ -1,6 +1,8 @@
|
|||
module github.com/go-redis/redis/v8
|
||||
|
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require (
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github.com/cespare/xxhash v1.1.0
|
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github.com/dgryski/go-rendezvous v0.0.0-20180401054734-3692eb46c031
|
||||
github.com/onsi/ginkgo v1.10.1
|
||||
github.com/onsi/gomega v1.7.0
|
||||
go.opentelemetry.io/otel v0.5.0
|
||||
|
|
|
|||
6
go.sum
6
go.sum
|
|
@ -2,14 +2,19 @@ cloud.google.com/go v0.26.0/go.mod h1:aQUYkXzVsufM+DwF1aE+0xfcU+56JwCaLick0ClmMT
|
|||
github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
|
||||
github.com/DataDog/sketches-go v0.0.0-20190923095040-43f19ad77ff7 h1:qELHH0AWCvf98Yf+CNIJx9vOZOfHFDDzgDRYsnNk/vs=
|
||||
github.com/DataDog/sketches-go v0.0.0-20190923095040-43f19ad77ff7/go.mod h1:Q5DbzQ+3AkgGwymQO7aZFNP7ns2lZKGtvRBzRXfdi60=
|
||||
github.com/OneOfOne/xxhash v1.2.2/go.mod h1:HSdplMjZKSmBqAxg5vPj2TmRDmfkzw+cTzAElWljhcU=
|
||||
github.com/benbjohnson/clock v1.0.0 h1:78Jk/r6m4wCi6sndMpty7A//t4dw/RW5fV4ZgDVfX1w=
|
||||
github.com/benbjohnson/clock v1.0.0/go.mod h1:bGMdMPoPVvcYyt1gHDf4J2KE153Yf9BuiUKYMaxlTDM=
|
||||
github.com/census-instrumentation/opencensus-proto v0.2.1/go.mod h1:f6KPmirojxKA12rnyqOA5BBL4O983OfeGPqjHWSTneU=
|
||||
github.com/cespare/xxhash v1.1.0 h1:a6HrQnmkObjyL+Gs60czilIUGqrzKutQD6XZog3p+ko=
|
||||
github.com/cespare/xxhash v1.1.0/go.mod h1:XrSqR1VqqWfGrhpAt58auRo0WTKS1nRRg3ghfAqPWnc=
|
||||
github.com/client9/misspell v0.3.4/go.mod h1:qj6jICC3Q7zFZvVWo7KLAzC3yx5G7kyvSDkc90ppPyw=
|
||||
github.com/cncf/udpa/go v0.0.0-20191209042840-269d4d468f6f/go.mod h1:M8M6+tZqaGXZJjfX53e64911xZQV5JYwmTeXPW+k8Sc=
|
||||
github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
|
||||
github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
|
||||
github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
|
||||
github.com/dgryski/go-rendezvous v0.0.0-20180401054734-3692eb46c031 h1:GqrUYGzmGuc00lpc+K0wwrqshfkKLwgYFJiCyOZFMVE=
|
||||
github.com/dgryski/go-rendezvous v0.0.0-20180401054734-3692eb46c031/go.mod h1:cuUVRXasLTGF7a8hSLbxyZXjz+1KgoB3wDUb6vlszIc=
|
||||
github.com/envoyproxy/go-control-plane v0.9.0/go.mod h1:YTl/9mNaCwkRvm6d1a2C3ymFceY/DCBVvsKhRF0iEA4=
|
||||
github.com/envoyproxy/go-control-plane v0.9.1-0.20191026205805-5f8ba28d4473/go.mod h1:YTl/9mNaCwkRvm6d1a2C3ymFceY/DCBVvsKhRF0iEA4=
|
||||
github.com/envoyproxy/go-control-plane v0.9.4/go.mod h1:6rpuAdCZL397s3pYoYcLgu1mIlRU8Am5FuJP05cCM98=
|
||||
|
|
@ -45,6 +50,7 @@ github.com/opentracing/opentracing-go v1.1.1-0.20190913142402-a7454ce5950e/go.mo
|
|||
github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
|
||||
github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
|
||||
github.com/prometheus/client_model v0.0.0-20190812154241-14fe0d1b01d4/go.mod h1:xMI15A0UPsDsEKsMN9yxemIoYk6Tm2C1GtYGdfGttqA=
|
||||
github.com/spaolacci/murmur3 v0.0.0-20180118202830-f09979ecbc72/go.mod h1:JwIasOWyU6f++ZhiEuf87xNszmSA2myDM2Kzu9HwQUA=
|
||||
github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
|
||||
github.com/stretchr/testify v1.4.0 h1:2E4SXV/wtOkTonXsotYi4li6zVWxYlZuYNCXe9XRJyk=
|
||||
github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
|
||||
|
|
|
|||
|
|
@ -1,81 +0,0 @@
|
|||
/*
|
||||
Copyright 2013 Google 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,
|
||||
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 consistenthash provides an implementation of a ring hash.
|
||||
package consistenthash
|
||||
|
||||
import (
|
||||
"hash/crc32"
|
||||
"sort"
|
||||
"strconv"
|
||||
)
|
||||
|
||||
type Hash func(data []byte) uint32
|
||||
|
||||
type Map struct {
|
||||
hash Hash
|
||||
replicas int
|
||||
keys []int // Sorted
|
||||
hashMap map[int]string
|
||||
}
|
||||
|
||||
func New(replicas int, fn Hash) *Map {
|
||||
m := &Map{
|
||||
replicas: replicas,
|
||||
hash: fn,
|
||||
hashMap: make(map[int]string),
|
||||
}
|
||||
if m.hash == nil {
|
||||
m.hash = crc32.ChecksumIEEE
|
||||
}
|
||||
return m
|
||||
}
|
||||
|
||||
// Returns true if there are no items available.
|
||||
func (m *Map) IsEmpty() bool {
|
||||
return len(m.keys) == 0
|
||||
}
|
||||
|
||||
// Adds some keys to the hash.
|
||||
func (m *Map) Add(keys ...string) {
|
||||
for _, key := range keys {
|
||||
for i := 0; i < m.replicas; i++ {
|
||||
hash := int(m.hash([]byte(strconv.Itoa(i) + key)))
|
||||
m.keys = append(m.keys, hash)
|
||||
m.hashMap[hash] = key
|
||||
}
|
||||
}
|
||||
sort.Ints(m.keys)
|
||||
}
|
||||
|
||||
// Gets the closest item in the hash to the provided key.
|
||||
func (m *Map) Get(key string) string {
|
||||
if m.IsEmpty() {
|
||||
return ""
|
||||
}
|
||||
|
||||
hash := int(m.hash([]byte(key)))
|
||||
|
||||
// Binary search for appropriate replica.
|
||||
idx := sort.Search(len(m.keys), func(i int) bool { return m.keys[i] >= hash })
|
||||
|
||||
// Means we have cycled back to the first replica.
|
||||
if idx == len(m.keys) {
|
||||
idx = 0
|
||||
}
|
||||
|
||||
return m.hashMap[m.keys[idx]]
|
||||
}
|
||||
|
|
@ -1,110 +0,0 @@
|
|||
/*
|
||||
Copyright 2013 Google 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,
|
||||
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 consistenthash
|
||||
|
||||
import (
|
||||
"fmt"
|
||||
"strconv"
|
||||
"testing"
|
||||
)
|
||||
|
||||
func TestHashing(t *testing.T) {
|
||||
|
||||
// Override the hash function to return easier to reason about values. Assumes
|
||||
// the keys can be converted to an integer.
|
||||
hash := New(3, func(key []byte) uint32 {
|
||||
i, err := strconv.Atoi(string(key))
|
||||
if err != nil {
|
||||
panic(err)
|
||||
}
|
||||
return uint32(i)
|
||||
})
|
||||
|
||||
// Given the above hash function, this will give replicas with "hashes":
|
||||
// 2, 4, 6, 12, 14, 16, 22, 24, 26
|
||||
hash.Add("6", "4", "2")
|
||||
|
||||
testCases := map[string]string{
|
||||
"2": "2",
|
||||
"11": "2",
|
||||
"23": "4",
|
||||
"27": "2",
|
||||
}
|
||||
|
||||
for k, v := range testCases {
|
||||
if hash.Get(k) != v {
|
||||
t.Errorf("Asking for %s, should have yielded %s", k, v)
|
||||
}
|
||||
}
|
||||
|
||||
// Adds 8, 18, 28
|
||||
hash.Add("8")
|
||||
|
||||
// 27 should now map to 8.
|
||||
testCases["27"] = "8"
|
||||
|
||||
for k, v := range testCases {
|
||||
if hash.Get(k) != v {
|
||||
t.Errorf("Asking for %s, should have yielded %s", k, v)
|
||||
}
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
func TestConsistency(t *testing.T) {
|
||||
hash1 := New(1, nil)
|
||||
hash2 := New(1, nil)
|
||||
|
||||
hash1.Add("Bill", "Bob", "Bonny")
|
||||
hash2.Add("Bob", "Bonny", "Bill")
|
||||
|
||||
if hash1.Get("Ben") != hash2.Get("Ben") {
|
||||
t.Errorf("Fetching 'Ben' from both hashes should be the same")
|
||||
}
|
||||
|
||||
hash2.Add("Becky", "Ben", "Bobby")
|
||||
|
||||
if hash1.Get("Ben") != hash2.Get("Ben") ||
|
||||
hash1.Get("Bob") != hash2.Get("Bob") ||
|
||||
hash1.Get("Bonny") != hash2.Get("Bonny") {
|
||||
t.Errorf("Direct matches should always return the same entry")
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
func BenchmarkGet8(b *testing.B) { benchmarkGet(b, 8) }
|
||||
func BenchmarkGet32(b *testing.B) { benchmarkGet(b, 32) }
|
||||
func BenchmarkGet128(b *testing.B) { benchmarkGet(b, 128) }
|
||||
func BenchmarkGet512(b *testing.B) { benchmarkGet(b, 512) }
|
||||
|
||||
func benchmarkGet(b *testing.B, shards int) {
|
||||
|
||||
hash := New(50, nil)
|
||||
|
||||
var buckets []string
|
||||
for i := 0; i < shards; i++ {
|
||||
buckets = append(buckets, fmt.Sprintf("shard-%d", i))
|
||||
}
|
||||
|
||||
hash.Add(buckets...)
|
||||
|
||||
b.ResetTimer()
|
||||
|
||||
for i := 0; i < b.N; i++ {
|
||||
hash.Get(buckets[i&(shards-1)])
|
||||
}
|
||||
}
|
||||
186
ring.go
186
ring.go
|
|
@ -10,55 +10,61 @@ import (
|
|||
"sync/atomic"
|
||||
"time"
|
||||
|
||||
"github.com/cespare/xxhash"
|
||||
"github.com/dgryski/go-rendezvous"
|
||||
|
||||
"github.com/go-redis/redis/v8/internal"
|
||||
"github.com/go-redis/redis/v8/internal/consistenthash"
|
||||
"github.com/go-redis/redis/v8/internal/hashtag"
|
||||
"github.com/go-redis/redis/v8/internal/pool"
|
||||
)
|
||||
|
||||
// Hash is type of hash function used in consistent hash.
|
||||
type Hash consistenthash.Hash
|
||||
|
||||
var errRingShardsDown = errors.New("redis: all ring shards are down")
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
|
||||
type ConsistentHash interface {
|
||||
Get(string) string
|
||||
}
|
||||
|
||||
type rendezvousWrapper struct {
|
||||
*rendezvous.Rendezvous
|
||||
}
|
||||
|
||||
func (w rendezvousWrapper) Get(key string) string {
|
||||
return w.Lookup(key)
|
||||
}
|
||||
|
||||
func newRendezvous(shards []string) ConsistentHash {
|
||||
return rendezvousWrapper{rendezvous.New(shards, xxhash.Sum64String)}
|
||||
}
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
|
||||
// RingOptions are used to configure a ring client and should be
|
||||
// passed to NewRing.
|
||||
type RingOptions struct {
|
||||
// Map of name => host:port addresses of ring shards.
|
||||
Addrs map[string]string
|
||||
|
||||
// NewClient creates a shard client with provided name and options.
|
||||
NewClient func(name string, opt *Options) *Client
|
||||
|
||||
// Frequency of PING commands sent to check shards availability.
|
||||
// Shard is considered down after 3 subsequent failed checks.
|
||||
HeartbeatFrequency time.Duration
|
||||
|
||||
// Hash function used in consistent hash.
|
||||
// Default is crc32.ChecksumIEEE.
|
||||
Hash Hash
|
||||
|
||||
// Number of replicas in consistent hash.
|
||||
// Default is 100 replicas.
|
||||
// NewConsistentHash returns a consistent hash that is used
|
||||
// to distribute keys across the shards.
|
||||
//
|
||||
// Higher number of replicas will provide less deviation, that is keys will be
|
||||
// distributed to nodes more evenly.
|
||||
//
|
||||
// Following is deviation for common nreplicas:
|
||||
// --------------------------------------------------------
|
||||
// | nreplicas | standard error | 99% confidence interval |
|
||||
// | 10 | 0.3152 | (0.37, 1.98) |
|
||||
// | 100 | 0.0997 | (0.76, 1.28) |
|
||||
// | 1000 | 0.0316 | (0.92, 1.09) |
|
||||
// --------------------------------------------------------
|
||||
//
|
||||
// See https://arxiv.org/abs/1406.2294 for reference
|
||||
HashReplicas int
|
||||
|
||||
// NewClient creates a shard client with provided name and options.
|
||||
NewClient func(name string, opt *Options) *Client
|
||||
// See https://medium.com/@dgryski/consistent-hashing-algorithmic-tradeoffs-ef6b8e2fcae8
|
||||
// for consistent hashing algorithmic tradeoffs.
|
||||
NewConsistentHash func(shards []string) ConsistentHash
|
||||
|
||||
// Following options are copied from Options struct.
|
||||
|
||||
OnConnect func(*Conn) error
|
||||
|
||||
Username string
|
||||
DB int
|
||||
Password string
|
||||
|
||||
|
|
@ -79,12 +85,18 @@ type RingOptions struct {
|
|||
}
|
||||
|
||||
func (opt *RingOptions) init() {
|
||||
if opt.NewClient == nil {
|
||||
opt.NewClient = func(name string, opt *Options) *Client {
|
||||
return NewClient(opt)
|
||||
}
|
||||
}
|
||||
|
||||
if opt.HeartbeatFrequency == 0 {
|
||||
opt.HeartbeatFrequency = 500 * time.Millisecond
|
||||
}
|
||||
|
||||
if opt.HashReplicas == 0 {
|
||||
opt.HashReplicas = 100
|
||||
if opt.NewConsistentHash == nil {
|
||||
opt.NewConsistentHash = newRendezvous
|
||||
}
|
||||
|
||||
switch opt.MinRetryBackoff {
|
||||
|
|
@ -127,6 +139,15 @@ type ringShard struct {
|
|||
down int32
|
||||
}
|
||||
|
||||
func newRingShard(opt *RingOptions, name, addr string) *ringShard {
|
||||
clopt := opt.clientOptions()
|
||||
clopt.Addr = addr
|
||||
|
||||
return &ringShard{
|
||||
Client: opt.NewClient(name, clopt),
|
||||
}
|
||||
}
|
||||
|
||||
func (shard *ringShard) String() string {
|
||||
var state string
|
||||
if shard.IsUp() {
|
||||
|
|
@ -168,40 +189,58 @@ type ringShards struct {
|
|||
opt *RingOptions
|
||||
|
||||
mu sync.RWMutex
|
||||
hash *consistenthash.Map
|
||||
hash ConsistentHash
|
||||
shards map[string]*ringShard // read only
|
||||
list []*ringShard // read only
|
||||
len int
|
||||
numShard int
|
||||
closed bool
|
||||
}
|
||||
|
||||
func newRingShards(opt *RingOptions) *ringShards {
|
||||
return &ringShards{
|
||||
shards := make(map[string]*ringShard, len(opt.Addrs))
|
||||
list := make([]*ringShard, 0, len(shards))
|
||||
|
||||
for name, addr := range opt.Addrs {
|
||||
shard := newRingShard(opt, name, addr)
|
||||
shards[name] = shard
|
||||
|
||||
list = append(list, shard)
|
||||
}
|
||||
|
||||
c := &ringShards{
|
||||
opt: opt,
|
||||
|
||||
hash: newConsistentHash(opt),
|
||||
shards: make(map[string]*ringShard),
|
||||
}
|
||||
shards: shards,
|
||||
list: list,
|
||||
}
|
||||
c.rebalance()
|
||||
|
||||
func (c *ringShards) Add(name string, cl *Client) {
|
||||
shard := &ringShard{Client: cl}
|
||||
c.hash.Add(name)
|
||||
c.shards[name] = shard
|
||||
c.list = append(c.list, shard)
|
||||
return c
|
||||
}
|
||||
|
||||
func (c *ringShards) List() []*ringShard {
|
||||
var list []*ringShard
|
||||
|
||||
c.mu.RLock()
|
||||
list := c.list
|
||||
if !c.closed {
|
||||
list = c.list
|
||||
}
|
||||
c.mu.RUnlock()
|
||||
|
||||
return list
|
||||
}
|
||||
|
||||
func (c *ringShards) Hash(key string) string {
|
||||
key = hashtag.Key(key)
|
||||
|
||||
var hash string
|
||||
|
||||
c.mu.RLock()
|
||||
hash := c.hash.Get(key)
|
||||
if c.numShard > 0 {
|
||||
hash = c.hash.Get(key)
|
||||
}
|
||||
c.mu.RUnlock()
|
||||
|
||||
return hash
|
||||
}
|
||||
|
||||
|
|
@ -215,6 +254,11 @@ func (c *ringShards) GetByKey(key string) (*ringShard, error) {
|
|||
return nil, pool.ErrClosed
|
||||
}
|
||||
|
||||
if c.numShard == 0 {
|
||||
c.mu.RUnlock()
|
||||
return nil, errRingShardsDown
|
||||
}
|
||||
|
||||
hash := c.hash.Get(key)
|
||||
if hash == "" {
|
||||
c.mu.RUnlock()
|
||||
|
|
@ -227,13 +271,13 @@ func (c *ringShards) GetByKey(key string) (*ringShard, error) {
|
|||
return shard, nil
|
||||
}
|
||||
|
||||
func (c *ringShards) GetByHash(name string) (*ringShard, error) {
|
||||
if name == "" {
|
||||
func (c *ringShards) GetByName(shardName string) (*ringShard, error) {
|
||||
if shardName == "" {
|
||||
return c.Random()
|
||||
}
|
||||
|
||||
c.mu.RLock()
|
||||
shard := c.shards[name]
|
||||
shard := c.shards[shardName]
|
||||
c.mu.RUnlock()
|
||||
return shard, nil
|
||||
}
|
||||
|
|
@ -247,23 +291,14 @@ func (c *ringShards) Heartbeat(frequency time.Duration) {
|
|||
ticker := time.NewTicker(frequency)
|
||||
defer ticker.Stop()
|
||||
|
||||
ctx := context.TODO()
|
||||
ctx := context.Background()
|
||||
for range ticker.C {
|
||||
var rebalance bool
|
||||
|
||||
c.mu.RLock()
|
||||
|
||||
if c.closed {
|
||||
c.mu.RUnlock()
|
||||
break
|
||||
}
|
||||
|
||||
shards := c.list
|
||||
c.mu.RUnlock()
|
||||
|
||||
for _, shard := range shards {
|
||||
for _, shard := range c.List() {
|
||||
err := shard.Client.Ping(ctx).Err()
|
||||
if shard.Vote(err == nil || err == pool.ErrPoolTimeout) {
|
||||
isUp := err == nil || err == pool.ErrPoolTimeout
|
||||
if shard.Vote(isUp) {
|
||||
internal.Logger.Printf("ring shard state changed: %s", shard)
|
||||
rebalance = true
|
||||
}
|
||||
|
|
@ -281,24 +316,25 @@ func (c *ringShards) rebalance() {
|
|||
shards := c.shards
|
||||
c.mu.RUnlock()
|
||||
|
||||
hash := newConsistentHash(c.opt)
|
||||
var shardsNum int
|
||||
liveShards := make([]string, 0, len(shards))
|
||||
|
||||
for name, shard := range shards {
|
||||
if shard.IsUp() {
|
||||
hash.Add(name)
|
||||
shardsNum++
|
||||
liveShards = append(liveShards, name)
|
||||
}
|
||||
}
|
||||
|
||||
hash := c.opt.NewConsistentHash(liveShards)
|
||||
|
||||
c.mu.Lock()
|
||||
c.hash = hash
|
||||
c.len = shardsNum
|
||||
c.numShard = len(liveShards)
|
||||
c.mu.Unlock()
|
||||
}
|
||||
|
||||
func (c *ringShards) Len() int {
|
||||
c.mu.RLock()
|
||||
l := c.len
|
||||
l := c.numShard
|
||||
c.mu.RUnlock()
|
||||
return l
|
||||
}
|
||||
|
|
@ -364,29 +400,15 @@ func NewRing(opt *RingOptions) *Ring {
|
|||
},
|
||||
ctx: context.Background(),
|
||||
}
|
||||
|
||||
ring.cmdsInfoCache = newCmdsInfoCache(ring.cmdsInfo)
|
||||
ring.cmdable = ring.Process
|
||||
|
||||
for name, addr := range opt.Addrs {
|
||||
shard := newRingShard(opt, name, addr)
|
||||
ring.shards.Add(name, shard)
|
||||
}
|
||||
|
||||
go ring.shards.Heartbeat(opt.HeartbeatFrequency)
|
||||
|
||||
return &ring
|
||||
}
|
||||
|
||||
func newRingShard(opt *RingOptions, name, addr string) *Client {
|
||||
clopt := opt.clientOptions()
|
||||
clopt.Addr = addr
|
||||
|
||||
if opt.NewClient != nil {
|
||||
return opt.NewClient(name, clopt)
|
||||
}
|
||||
return NewClient(clopt)
|
||||
}
|
||||
|
||||
func (c *Ring) Context() context.Context {
|
||||
return c.ctx
|
||||
}
|
||||
|
|
@ -623,7 +645,7 @@ func (c *Ring) generalProcessPipeline(
|
|||
cmdInfo := c.cmdInfo(cmd.Name())
|
||||
hash := cmd.stringArg(cmdFirstKeyPos(cmd, cmdInfo))
|
||||
if hash != "" {
|
||||
hash = c.shards.Hash(hashtag.Key(hash))
|
||||
hash = c.shards.Hash(hash)
|
||||
}
|
||||
cmdsMap[hash] = append(cmdsMap[hash], cmd)
|
||||
}
|
||||
|
|
@ -646,7 +668,7 @@ func (c *Ring) processShardPipeline(
|
|||
ctx context.Context, hash string, cmds []Cmder, tx bool,
|
||||
) error {
|
||||
//TODO: retry?
|
||||
shard, err := c.shards.GetByHash(hash)
|
||||
shard, err := c.shards.GetByName(hash)
|
||||
if err != nil {
|
||||
setCmdsErr(cmds, err)
|
||||
return err
|
||||
|
|
@ -700,7 +722,3 @@ func (c *Ring) Watch(ctx context.Context, fn func(*Tx) error, keys ...string) er
|
|||
|
||||
return shards[0].Client.Watch(ctx, fn, keys...)
|
||||
}
|
||||
|
||||
func newConsistentHash(opt *RingOptions) *consistenthash.Map {
|
||||
return consistenthash.New(opt.HashReplicas, consistenthash.Hash(opt.Hash))
|
||||
}
|
||||
|
|
|
|||
24
ring_test.go
24
ring_test.go
|
|
@ -54,8 +54,8 @@ var _ = Describe("Redis Ring", func() {
|
|||
setRingKeys()
|
||||
|
||||
// Both shards should have some keys now.
|
||||
Expect(ringShard1.Info(ctx, "keyspace").Val()).To(ContainSubstring("keys=57"))
|
||||
Expect(ringShard2.Info(ctx, "keyspace").Val()).To(ContainSubstring("keys=43"))
|
||||
Expect(ringShard1.Info(ctx, "keyspace").Val()).To(ContainSubstring("keys=56"))
|
||||
Expect(ringShard2.Info(ctx, "keyspace").Val()).To(ContainSubstring("keys=44"))
|
||||
})
|
||||
|
||||
It("distributes keys when using EVAL", func() {
|
||||
|
|
@ -71,8 +71,8 @@ var _ = Describe("Redis Ring", func() {
|
|||
Expect(err).NotTo(HaveOccurred())
|
||||
}
|
||||
|
||||
Expect(ringShard1.Info(ctx, "keyspace").Val()).To(ContainSubstring("keys=57"))
|
||||
Expect(ringShard2.Info(ctx, "keyspace").Val()).To(ContainSubstring("keys=43"))
|
||||
Expect(ringShard1.Info(ctx, "keyspace").Val()).To(ContainSubstring("keys=56"))
|
||||
Expect(ringShard2.Info(ctx, "keyspace").Val()).To(ContainSubstring("keys=44"))
|
||||
})
|
||||
|
||||
It("uses single shard when one of the shards is down", func() {
|
||||
|
|
@ -100,7 +100,7 @@ var _ = Describe("Redis Ring", func() {
|
|||
setRingKeys()
|
||||
|
||||
// RingShard2 should have its keys.
|
||||
Expect(ringShard2.Info(ctx, "keyspace").Val()).To(ContainSubstring("keys=43"))
|
||||
Expect(ringShard2.Info(ctx, "keyspace").Val()).To(ContainSubstring("keys=44"))
|
||||
})
|
||||
|
||||
It("supports hash tags", func() {
|
||||
|
|
@ -131,8 +131,8 @@ var _ = Describe("Redis Ring", func() {
|
|||
}
|
||||
|
||||
// Both shards should have some keys now.
|
||||
Expect(ringShard1.Info(ctx).Val()).To(ContainSubstring("keys=57"))
|
||||
Expect(ringShard2.Info(ctx).Val()).To(ContainSubstring("keys=43"))
|
||||
Expect(ringShard1.Info(ctx).Val()).To(ContainSubstring("keys=56"))
|
||||
Expect(ringShard2.Info(ctx).Val()).To(ContainSubstring("keys=44"))
|
||||
})
|
||||
|
||||
It("is consistent with ring", func() {
|
||||
|
|
@ -427,22 +427,22 @@ var _ = Describe("Ring watch", func() {
|
|||
It("should discard", func() {
|
||||
err := ring.Watch(ctx, func(tx *redis.Tx) error {
|
||||
cmds, err := tx.TxPipelined(ctx, func(pipe redis.Pipeliner) error {
|
||||
pipe.Set(ctx, "key1", "hello1", 0)
|
||||
pipe.Set(ctx, "{shard}key1", "hello1", 0)
|
||||
pipe.Discard()
|
||||
pipe.Set(ctx, "key2", "hello2", 0)
|
||||
pipe.Set(ctx, "{shard}key2", "hello2", 0)
|
||||
return nil
|
||||
})
|
||||
Expect(err).NotTo(HaveOccurred())
|
||||
Expect(cmds).To(HaveLen(1))
|
||||
return err
|
||||
}, "key1", "key2")
|
||||
}, "{shard}key1", "{shard}key2")
|
||||
Expect(err).NotTo(HaveOccurred())
|
||||
|
||||
get := ring.Get(ctx, "key1")
|
||||
get := ring.Get(ctx, "{shard}key1")
|
||||
Expect(get.Err()).To(Equal(redis.Nil))
|
||||
Expect(get.Val()).To(Equal(""))
|
||||
|
||||
get = ring.Get(ctx, "key2")
|
||||
get = ring.Get(ctx, "{shard}key2")
|
||||
Expect(get.Err()).NotTo(HaveOccurred())
|
||||
Expect(get.Val()).To(Equal("hello2"))
|
||||
})
|
||||
|
|
|
|||
Loading…
Reference in New Issue