Files
tidb/br/pkg/lightning/backend/external/split_test.go
2023-09-05 02:02:11 +00:00

337 lines
11 KiB
Go

// Copyright 2023 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,
// 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 external
import (
"bytes"
"context"
"fmt"
"math"
"testing"
"time"
"github.com/pingcap/tidb/br/pkg/storage"
"github.com/pingcap/tidb/kv"
"github.com/stretchr/testify/require"
"golang.org/x/exp/rand"
)
func TestGeneralProperties(t *testing.T) {
seed := time.Now().Unix()
rand.Seed(uint64(seed))
t.Logf("seed: %d", seed)
ctx := context.Background()
memStore := storage.NewMemStorage()
kvNum := rand.Intn(1000) + 100
keys := make([][]byte, kvNum)
values := make([][]byte, kvNum)
for i := range keys {
keyLen := rand.Intn(100) + 1
valueLen := rand.Intn(100) + 1
keys[i] = make([]byte, keyLen)
values[i] = make([]byte, valueLen)
rand.Read(keys[i])
rand.Read(values[i])
}
dataFiles, statFiles, err := MockExternalEngine(memStore, keys, values)
require.NoError(t, err)
splitter, err := NewRangeSplitter(
ctx, dataFiles, statFiles, memStore, 1000, 30, 1000, 1,
)
var lastEndKey []byte
notExhausted:
endKey, dataFiles, statFiles, splitKeys, err := splitter.SplitOneRangesGroup()
require.NoError(t, err)
// endKey should be strictly greater than lastEndKey
if lastEndKey != nil && endKey != nil {
cmp := bytes.Compare(endKey, lastEndKey)
require.Equal(t, 1, cmp, "endKey: %v, lastEndKey: %v", endKey, lastEndKey)
}
// check dataFiles and statFiles
lenDataFiles := len(dataFiles)
lenStatFiles := len(statFiles)
require.Equal(t, lenDataFiles, lenStatFiles)
require.Greater(t, lenDataFiles, 0)
require.Greater(t, len(splitKeys), 0)
// splitKeys should be strictly increasing
for i := 1; i < len(splitKeys); i++ {
cmp := bytes.Compare(splitKeys[i], splitKeys[i-1])
require.Equal(t, 1, cmp, "splitKeys: %v", splitKeys)
}
// first splitKeys should be strictly greater than lastEndKey
cmp := bytes.Compare(splitKeys[0], lastEndKey)
require.Equal(t, 1, cmp, "splitKeys: %v, lastEndKey: %v", splitKeys, lastEndKey)
// last splitKeys should be strictly less than endKey
if endKey != nil {
cmp = bytes.Compare(splitKeys[len(splitKeys)-1], endKey)
require.Equal(t, -1, cmp, "splitKeys: %v, endKey: %v", splitKeys, endKey)
}
lastEndKey = endKey
if endKey != nil {
goto notExhausted
}
require.NoError(t, splitter.Close())
}
func TestOnlyOneGroup(t *testing.T) {
ctx := context.Background()
memStore := storage.NewMemStorage()
subDir := "/mock-test"
writer := NewWriterBuilder().
SetMemorySizeLimit(15).
SetPropSizeDistance(1).
SetPropKeysDistance(1).
Build(memStore, subDir, 5)
dataFiles, statFiles, err := MockExternalEngineWithWriter(memStore, writer, subDir, [][]byte{{1}, {2}}, [][]byte{{1}, {2}})
require.NoError(t, err)
splitter, err := NewRangeSplitter(
ctx, dataFiles, statFiles, memStore, 1000, 30, 1000, 10,
)
require.NoError(t, err)
endKey, dataFiles, statFiles, splitKeys, err := splitter.SplitOneRangesGroup()
require.NoError(t, err)
require.Nil(t, endKey)
require.Len(t, dataFiles, 1)
require.Len(t, statFiles, 1)
require.Len(t, splitKeys, 0)
require.NoError(t, splitter.Close())
splitter, err = NewRangeSplitter(
ctx, dataFiles, statFiles, memStore, 1000, 30, 1000, 1,
)
require.NoError(t, err)
endKey, dataFiles, statFiles, splitKeys, err = splitter.SplitOneRangesGroup()
require.NoError(t, err)
require.Nil(t, endKey)
require.Len(t, dataFiles, 1)
require.Len(t, statFiles, 1)
require.Equal(t, [][]byte{{2}}, splitKeys)
require.NoError(t, splitter.Close())
}
func TestSortedData(t *testing.T) {
ctx := context.Background()
memStore := storage.NewMemStorage()
kvNum := 100
keys := make([][]byte, kvNum)
values := make([][]byte, kvNum)
for i := range keys {
keys[i] = []byte(fmt.Sprintf("key%03d", i))
values[i] = []byte(fmt.Sprintf("value%03d", i))
}
dataFiles, statFiles, err := MockExternalEngine(memStore, keys, values)
require.NoError(t, err)
// we just need to make sure there are multiple files.
require.Greater(t, len(dataFiles), 1)
avgKVPerFile := math.Ceil(float64(kvNum) / float64(len(dataFiles)))
rangesGroupKV := 30
groupFileNumUpperBound := int(math.Ceil(float64(rangesGroupKV-1)/avgKVPerFile)) + 1
splitter, err := NewRangeSplitter(
ctx, dataFiles, statFiles, memStore, 1000, int64(rangesGroupKV), 1000, 10,
)
require.NoError(t, err)
notExhausted:
endKey, dataFiles, statFiles, _, err := splitter.SplitOneRangesGroup()
require.NoError(t, err)
require.LessOrEqual(t, len(dataFiles), groupFileNumUpperBound)
require.LessOrEqual(t, len(statFiles), groupFileNumUpperBound)
if endKey != nil {
goto notExhausted
}
require.NoError(t, splitter.Close())
}
func TestRangeSplitterStrictCase(t *testing.T) {
ctx := context.Background()
memStore := storage.NewMemStorage()
subDir := "/mock-test"
writer1 := NewWriterBuilder().
SetMemorySizeLimit(15). // slightly larger than len("key01") + len("value01")
SetPropSizeDistance(1).
SetPropKeysDistance(1).
Build(memStore, subDir, 1)
keys1 := [][]byte{
[]byte("key01"), []byte("key11"), []byte("key21"),
}
values1 := [][]byte{
[]byte("value01"), []byte("value11"), []byte("value21"),
}
dataFiles1, statFiles1, err := MockExternalEngineWithWriter(memStore, writer1, subDir, keys1, values1)
require.NoError(t, err)
require.Len(t, dataFiles1, 2)
require.Len(t, statFiles1, 2)
writer2 := NewWriterBuilder().
SetMemorySizeLimit(15).
SetPropSizeDistance(1).
SetPropKeysDistance(1).
Build(memStore, subDir, 2)
keys2 := [][]byte{
[]byte("key02"), []byte("key12"), []byte("key22"),
}
values2 := [][]byte{
[]byte("value02"), []byte("value12"), []byte("value22"),
}
dataFiles12, statFiles12, err := MockExternalEngineWithWriter(memStore, writer2, subDir, keys2, values2)
require.NoError(t, err)
require.Len(t, dataFiles12, 4)
require.Len(t, statFiles12, 4)
writer3 := NewWriterBuilder().
SetMemorySizeLimit(15).
SetPropSizeDistance(1).
SetPropKeysDistance(1).
Build(memStore, subDir, 3)
keys3 := [][]byte{
[]byte("key03"), []byte("key13"), []byte("key23"),
}
values3 := [][]byte{
[]byte("value03"), []byte("value13"), []byte("value23"),
}
dataFiles123, statFiles123, err := MockExternalEngineWithWriter(memStore, writer3, subDir, keys3, values3)
require.NoError(t, err)
require.Len(t, dataFiles123, 6)
require.Len(t, statFiles123, 6)
// "/mock-test/X/0" contains "key0X" and "key1X"
// "/mock-test/X/1" contains "key2X"
require.Equal(t, []string{
"/mock-test/1/0", "/mock-test/1/1",
"/mock-test/2/0", "/mock-test/2/1",
"/mock-test/3/0", "/mock-test/3/1",
}, dataFiles123)
// group keys = 2, region keys = 1
splitter, err := NewRangeSplitter(
ctx, dataFiles123, statFiles123, memStore, 1000, 2, 1000, 1,
)
require.NoError(t, err)
// [key01, key03), split at key02
endKey, dataFiles, statFiles, splitKeys, err := splitter.SplitOneRangesGroup()
require.NoError(t, err)
require.EqualValues(t, kv.Key("key03"), endKey)
require.Equal(t, []string{"/mock-test/1/0", "/mock-test/2/0"}, dataFiles)
require.Equal(t, []string{"/mock-test/1_stat/0", "/mock-test/2_stat/0"}, statFiles)
require.Equal(t, [][]byte{[]byte("key02")}, splitKeys)
// [key03, key12), split at key11
endKey, dataFiles, statFiles, splitKeys, err = splitter.SplitOneRangesGroup()
require.NoError(t, err)
require.EqualValues(t, kv.Key("key12"), endKey)
require.Equal(t, []string{"/mock-test/1/0", "/mock-test/2/0", "/mock-test/3/0"}, dataFiles)
require.Equal(t, []string{"/mock-test/1_stat/0", "/mock-test/2_stat/0", "/mock-test/3_stat/0"}, statFiles)
require.Equal(t, [][]byte{[]byte("key11")}, splitKeys)
// [key12, key21), split at key13. the last key of "/mock-test/1/0" is "key11",
// so it's not used
endKey, dataFiles, statFiles, splitKeys, err = splitter.SplitOneRangesGroup()
require.NoError(t, err)
require.EqualValues(t, kv.Key("key21"), endKey)
require.Equal(t, []string{"/mock-test/2/0", "/mock-test/3/0"}, dataFiles)
require.Equal(t, []string{"/mock-test/2_stat/0", "/mock-test/3_stat/0"}, statFiles)
require.Equal(t, [][]byte{[]byte("key13")}, splitKeys)
// [key21, key23), split at key22.
// the last key of "/mock-test/2/0" is "key12", and the last key of "/mock-test/3/0" is "key13",
// so they are not used
endKey, dataFiles, statFiles, splitKeys, err = splitter.SplitOneRangesGroup()
require.NoError(t, err)
require.EqualValues(t, kv.Key("key23"), endKey)
require.Equal(t, []string{"/mock-test/1/1", "/mock-test/2/1"}, dataFiles)
require.Equal(t, []string{"/mock-test/1_stat/1", "/mock-test/2_stat/1"}, statFiles)
require.Equal(t, [][]byte{[]byte("key22")}, splitKeys)
// [key23, nil), no split key
endKey, dataFiles, statFiles, splitKeys, err = splitter.SplitOneRangesGroup()
require.NoError(t, err)
require.Nil(t, endKey)
require.Equal(t, []string{"/mock-test/3/1"}, dataFiles)
require.Equal(t, []string{"/mock-test/3_stat/1"}, statFiles)
require.Len(t, splitKeys, 0)
// read after drain all data
endKey, dataFiles, statFiles, splitKeys, err = splitter.SplitOneRangesGroup()
require.NoError(t, err)
require.Nil(t, endKey)
require.Len(t, dataFiles, 0)
require.Len(t, statFiles, 0)
require.Len(t, splitKeys, 0)
require.NoError(t, splitter.Close())
}
func TestExactlyKeyNum(t *testing.T) {
ctx := context.Background()
memStore := storage.NewMemStorage()
kvNum := 3
keys := make([][]byte, kvNum)
values := make([][]byte, kvNum)
for i := range keys {
keys[i] = []byte(fmt.Sprintf("key%03d", i))
values[i] = []byte(fmt.Sprintf("value%03d", i))
}
subDir := "/mock-test"
writer := NewWriterBuilder().
SetMemorySizeLimit(15).
SetPropSizeDistance(1).
SetPropKeysDistance(1).
Build(memStore, subDir, 5)
dataFiles, statFiles, err := MockExternalEngineWithWriter(memStore, writer, subDir, keys, values)
require.NoError(t, err)
// maxRangeKeys = 3
splitter, err := NewRangeSplitter(
ctx, dataFiles, statFiles, memStore, 1000, 100, 1000, 3,
)
require.NoError(t, err)
endKey, splitDataFiles, splitStatFiles, splitKeys, err := splitter.SplitOneRangesGroup()
require.NoError(t, err)
require.Nil(t, endKey)
require.Equal(t, dataFiles, splitDataFiles)
require.Equal(t, statFiles, splitStatFiles)
require.Len(t, splitKeys, 0)
// rangesGroupKeys = 3
splitter, err = NewRangeSplitter(
ctx, dataFiles, statFiles, memStore, 1000, 3, 1000, 1,
)
require.NoError(t, err)
endKey, splitDataFiles, splitStatFiles, splitKeys, err = splitter.SplitOneRangesGroup()
require.NoError(t, err)
require.Nil(t, endKey)
require.Equal(t, dataFiles, splitDataFiles)
require.Equal(t, statFiles, splitStatFiles)
require.Equal(t, [][]byte{[]byte("key001"), []byte("key002")}, splitKeys)
}