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stream_writer_test.go
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stream_writer_test.go
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/*
* Copyright 2019 Dgraph Labs, Inc. and Contributors
*
* 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 badger
import (
"bytes"
"encoding/binary"
"fmt"
"io/ioutil"
"math"
"math/rand"
"os"
"testing"
"github.com/stretchr/testify/require"
"github.com/0x5459/badger/v4/pb"
"github.com/0x5459/badger/v4/y"
"github.com/dgraph-io/ristretto/z"
)
func getSortedKVList(valueSize, listSize int) *z.Buffer {
value := make([]byte, valueSize)
y.Check2(rand.Read(value))
buf := z.NewBuffer(10<<20, "test")
for i := 0; i < listSize; i++ {
key := make([]byte, 8)
binary.BigEndian.PutUint64(key, uint64(i))
KVToBuffer(&pb.KV{
Key: key,
Value: value,
Version: 20,
}, buf)
}
return buf
}
// check if we can read values after writing using stream writer
func TestStreamWriter1(t *testing.T) {
test := func(t *testing.T, opts *Options) {
runBadgerTest(t, opts, func(t *testing.T, db *DB) {
// write entries using stream writer
noOfKeys := 10
valueSize := 128
list := getSortedKVList(valueSize, noOfKeys)
sw := db.NewStreamWriter()
require.NoError(t, sw.Prepare(), "sw.Prepare() failed")
require.NoError(t, sw.Write(list), "sw.Write() failed")
require.NoError(t, sw.Flush(), "sw.Flush() failed")
err := db.View(func(txn *Txn) error {
// read any random key from inserted keys
keybyte := make([]byte, 8)
keyNo := uint64(rand.Int63n(int64(noOfKeys)))
binary.BigEndian.PutUint64(keybyte, keyNo)
_, err := txn.Get(keybyte)
require.Nil(t, err, "key should be found")
// count all keys written using stream writer
keysCount := 0
itrOps := DefaultIteratorOptions
it := txn.NewIterator(itrOps)
defer it.Close()
for it.Rewind(); it.Valid(); it.Next() {
keysCount++
}
require.True(t, keysCount == noOfKeys, "count of keys should be matched")
return nil
})
require.NoError(t, err, "error while retrieving key")
})
}
t.Run("Normal mode", func(t *testing.T) {
normalModeOpts := getTestOptions("")
test(t, &normalModeOpts)
})
t.Run("Managed mode", func(t *testing.T) {
managedModeOpts := getTestOptions("")
managedModeOpts.managedTxns = true
test(t, &managedModeOpts)
})
t.Run("InMemory mode", func(t *testing.T) {
diskLessModeOpts := getTestOptions("")
diskLessModeOpts.InMemory = true
test(t, &diskLessModeOpts)
})
}
// write more keys to db after writing keys using stream writer
func TestStreamWriter2(t *testing.T) {
test := func(t *testing.T, opts *Options) {
runBadgerTest(t, opts, func(t *testing.T, db *DB) {
// write entries using stream writer
noOfKeys := 1000
valueSize := 128
list := getSortedKVList(valueSize, noOfKeys)
sw := db.NewStreamWriter()
require.NoError(t, sw.Prepare(), "sw.Prepare() failed")
require.NoError(t, sw.Write(list), "sw.Write() failed")
// get max version of sw, will be used in transactions for managed mode
maxVs := sw.maxVersion
require.NoError(t, sw.Flush(), "sw.Flush() failed")
// delete all the inserted keys
val := make([]byte, valueSize)
y.Check2(rand.Read(val))
for i := 0; i < noOfKeys; i++ {
txn := db.newTransaction(true, opts.managedTxns)
if opts.managedTxns {
txn.readTs = math.MaxUint64
txn.commitTs = maxVs
}
keybyte := make([]byte, 8)
keyNo := uint64(i)
binary.BigEndian.PutUint64(keybyte, keyNo)
require.NoError(t, txn.Delete(keybyte), "error while deleting keys")
require.NoError(t, txn.Commit(), "error while commit")
}
// verify while iteration count of keys should be 0
err := db.View(func(txn *Txn) error {
keysCount := 0
itrOps := DefaultIteratorOptions
it := txn.NewIterator(itrOps)
defer it.Close()
for it.Rewind(); it.Valid(); it.Next() {
keysCount++
}
require.Zero(t, keysCount, "count of keys should be 0")
return nil
})
require.Nil(t, err, "error should be nil while iterating")
})
}
t.Run("Normal mode", func(t *testing.T) {
normalModeOpts := getTestOptions("")
test(t, &normalModeOpts)
})
t.Run("Managed mode", func(t *testing.T) {
managedModeOpts := getTestOptions("")
managedModeOpts.managedTxns = true
test(t, &managedModeOpts)
})
t.Run("InMemory mode", func(t *testing.T) {
diskLessModeOpts := getTestOptions("")
diskLessModeOpts.InMemory = true
test(t, &diskLessModeOpts)
})
}
func TestStreamWriter3(t *testing.T) {
test := func(t *testing.T, opts *Options) {
runBadgerTest(t, opts, func(t *testing.T, db *DB) {
// write entries using stream writer
noOfKeys := 1000
valueSize := 128
// insert keys which are even
value := make([]byte, valueSize)
y.Check2(rand.Read(value))
counter := 0
buf := z.NewBuffer(10<<20, "test")
defer buf.Release()
for i := 0; i < noOfKeys; i++ {
key := make([]byte, 8)
binary.BigEndian.PutUint64(key, uint64(counter))
KVToBuffer(&pb.KV{
Key: key,
Value: value,
Version: 20,
}, buf)
counter = counter + 2
}
sw := db.NewStreamWriter()
require.NoError(t, sw.Prepare(), "sw.Prepare() failed")
require.NoError(t, sw.Write(buf), "sw.Write() failed")
// get max version of sw, will be used in transactions for managed mode
maxVs := sw.maxVersion
require.NoError(t, sw.Flush(), "sw.Flush() failed")
// insert keys which are odd
val := make([]byte, valueSize)
y.Check2(rand.Read(val))
counter = 1
for i := 0; i < noOfKeys; i++ {
txn := db.newTransaction(true, opts.managedTxns)
if opts.managedTxns {
txn.readTs = math.MaxUint64
txn.commitTs = maxVs
}
keybyte := make([]byte, 8)
keyNo := uint64(counter)
binary.BigEndian.PutUint64(keybyte, keyNo)
require.NoError(t, txn.SetEntry(NewEntry(keybyte, val)),
"error while inserting entries")
require.NoError(t, txn.Commit(), "error while commit")
counter = counter + 2
}
// verify while iteration keys are in sorted order
err := db.View(func(txn *Txn) error {
keysCount := 0
itrOps := DefaultIteratorOptions
it := txn.NewIterator(itrOps)
defer it.Close()
prev := uint64(0)
for it.Rewind(); it.Valid(); it.Next() {
item := it.Item()
key := item.Key()
current := binary.BigEndian.Uint64(key)
if prev != 0 && current != (prev+uint64(1)) {
t.Fatal("keys should be in increasing order")
}
keysCount++
prev = current
}
require.True(t, keysCount == 2*noOfKeys, "count of keys is not matching")
return nil
})
require.Nil(t, err, "error should be nil while iterating")
})
}
t.Run("Normal mode", func(t *testing.T) {
normalModeOpts := getTestOptions("")
test(t, &normalModeOpts)
})
t.Run("Managed mode", func(t *testing.T) {
managedModeOpts := getTestOptions("")
managedModeOpts.managedTxns = true
test(t, &managedModeOpts)
})
t.Run("InMemory mode", func(t *testing.T) {
diskLessModeOpts := getTestOptions("")
diskLessModeOpts.InMemory = true
test(t, &diskLessModeOpts)
})
}
// After inserting all data from streams, StreamWriter reinitializes Oracle and updates its nextTs
// to maxVersion found in all entries inserted(if db is running in non managed mode). It also
// updates Oracle's txnMark and readMark. If Oracle is not reinitialized, it might cause issue
// while updating readMark and txnMark when its nextTs is ahead of maxVersion. This tests verifies
// Oracle reinitialization is happening. Try commenting line 171 in stream_writer.go with code
// (sw.db.orc = newOracle(sw.db.opt), this test should fail.
func TestStreamWriter4(t *testing.T) {
runBadgerTest(t, nil, func(t *testing.T, db *DB) {
// first insert some entries in db
for i := 0; i < 10; i++ {
err := db.Update(func(txn *Txn) error {
key := []byte(fmt.Sprintf("key-%d", i))
value := []byte(fmt.Sprintf("val-%d", i))
return txn.Set(key, value)
})
require.NoError(t, err, "error while updating db")
}
buf := z.NewBuffer(10<<20, "test")
defer buf.Release()
KVToBuffer(&pb.KV{
Key: []byte("key-1"),
Value: []byte("value-1"),
Version: 1,
}, buf)
sw := db.NewStreamWriter()
require.NoError(t, sw.Prepare(), "sw.Prepare() failed")
require.NoError(t, sw.Write(buf), "sw.Write() failed")
require.NoError(t, sw.Flush(), "sw.Flush() failed")
})
}
func TestStreamWriter5(t *testing.T) {
runBadgerTest(t, nil, func(t *testing.T, db *DB) {
left := make([]byte, 6)
left[0] = 0x00
copy(left[1:], []byte("break"))
right := make([]byte, 6)
right[0] = 0xff
copy(right[1:], []byte("break"))
buf := z.NewBuffer(10<<20, "test")
defer buf.Release()
KVToBuffer(&pb.KV{
Key: left,
Value: []byte("val"),
Version: 1,
}, buf)
KVToBuffer(&pb.KV{
Key: right,
Value: []byte("val"),
Version: 1,
}, buf)
sw := db.NewStreamWriter()
require.NoError(t, sw.Prepare(), "sw.Prepare() failed")
require.NoError(t, sw.Write(buf), "sw.Write() failed")
require.NoError(t, sw.Flush(), "sw.Flush() failed")
require.NoError(t, db.Close())
var err error
db, err = Open(db.opt)
require.NoError(t, err)
require.NoError(t, db.Close())
})
}
// This test tries to insert multiple equal keys(without version) and verifies
// if those are going to same table.
func TestStreamWriter6(t *testing.T) {
opt := getTestOptions("")
opt.BaseTableSize = 1 << 15
runBadgerTest(t, &opt, func(t *testing.T, db *DB) {
str := []string{"a", "b", "c"}
ver := uint64(0)
// The baseTable size is 32 KB (1<<15) and the max table size for level
// 6 table is 1 mb (look at newWrite function). Since all the tables
// will be written to level 6, we need to insert at least 1 mb of data.
// Setting keycount below 32 would cause this test to fail.
keyCount := 40
buf := z.NewBuffer(10<<20, "test")
defer buf.Release()
for i := range str {
for j := 0; j < keyCount; j++ {
ver++
kv := &pb.KV{
Key: bytes.Repeat([]byte(str[i]), int(db.opt.BaseTableSize)),
Value: []byte("val"),
Version: uint64(keyCount - j),
}
KVToBuffer(kv, buf)
}
}
// list has 3 pairs for equal keys. Since each Key has size equal to MaxTableSize
// we would have 6 tables, if keys are not equal. Here we should have 3 tables.
sw := db.NewStreamWriter()
require.NoError(t, sw.Prepare(), "sw.Prepare() failed")
require.NoError(t, sw.Write(buf), "sw.Write() failed")
require.NoError(t, sw.Flush(), "sw.Flush() failed")
tables := db.Tables()
require.Equal(t, 3, len(tables), "Count of tables not matching")
for _, tab := range tables {
require.Equal(t, keyCount, int(tab.KeyCount),
fmt.Sprintf("failed for level: %d", tab.Level))
}
require.NoError(t, db.Close())
db, err := Open(db.opt)
require.NoError(t, err)
require.NoError(t, db.Close())
})
}
// This test uses a StreamWriter without calling Flush() at the end.
func TestStreamWriterCancel(t *testing.T) {
opt := getTestOptions("")
opt.BaseTableSize = 1 << 15
runBadgerTest(t, &opt, func(t *testing.T, db *DB) {
str := []string{"a", "a", "b", "b", "c", "c"}
ver := 1
buf := z.NewBuffer(10<<20, "test")
defer buf.Release()
for i := range str {
kv := &pb.KV{
Key: bytes.Repeat([]byte(str[i]), int(db.opt.BaseTableSize)),
Value: []byte("val"),
Version: uint64(ver),
}
KVToBuffer(kv, buf)
ver = (ver + 1) % 2
}
sw := db.NewStreamWriter()
require.NoError(t, sw.Prepare(), "sw.Prepare() failed")
require.NoError(t, sw.Write(buf), "sw.Write() failed")
sw.Cancel()
// Use the API incorrectly.
sw1 := db.NewStreamWriter()
defer sw1.Cancel()
require.NoError(t, sw1.Prepare())
defer sw1.Cancel()
sw1.Flush()
})
}
func TestStreamDone(t *testing.T) {
runBadgerTest(t, nil, func(t *testing.T, db *DB) {
sw := db.NewStreamWriter()
require.NoError(t, sw.Prepare(), "sw.Prepare() failed")
var val [10]byte
rand.Read(val[:])
for i := 0; i < 10; i++ {
buf := z.NewBuffer(10<<20, "test")
defer buf.Release()
kv1 := &pb.KV{
Key: []byte(fmt.Sprintf("%d", i)),
Value: val[:],
Version: 1,
StreamId: uint32(i),
}
kv2 := &pb.KV{
StreamId: uint32(i),
StreamDone: true,
}
KVToBuffer(kv1, buf)
KVToBuffer(kv2, buf)
require.NoError(t, sw.Write(buf), "sw.Write() failed")
}
require.NoError(t, sw.Flush(), "sw.Flush() failed")
require.NoError(t, db.Close())
var err error
db, err = Open(db.opt)
require.NoError(t, err)
require.NoError(t, db.Close())
})
}
func TestSendOnClosedStream(t *testing.T) {
dir, err := ioutil.TempDir("", "badger-test")
require.NoError(t, err)
defer func() {
require.NoError(t, os.RemoveAll(dir))
}()
opts := getTestOptions(dir)
db, err := Open(opts)
require.NoError(t, err)
sw := db.NewStreamWriter()
require.NoError(t, sw.Prepare(), "sw.Prepare() failed")
var val [10]byte
rand.Read(val[:])
buf := z.NewBuffer(10<<20, "test")
defer buf.Release()
kv1 := &pb.KV{
Key: []byte(fmt.Sprintf("%d", 1)),
Value: val[:],
Version: 1,
StreamId: uint32(1),
}
kv2 := &pb.KV{
StreamId: uint32(1),
StreamDone: true,
}
KVToBuffer(kv1, buf)
KVToBuffer(kv2, buf)
require.NoError(t, sw.Write(buf), "sw.Write() failed")
// Defer for panic.
defer func() {
require.NotNil(t, recover(), "should have paniced")
require.NoError(t, sw.Flush())
require.NoError(t, db.Close())
}()
// Send once stream is closed.
buf1 := z.NewBuffer(10<<20, "test")
defer buf1.Release()
kv1 = &pb.KV{
Key: []byte(fmt.Sprintf("%d", 2)),
Value: val[:],
Version: 1,
StreamId: uint32(1),
}
KVToBuffer(kv1, buf1)
sw.Write(buf1)
}
func TestSendOnClosedStream2(t *testing.T) {
dir, err := ioutil.TempDir("", "badger-test")
require.NoError(t, err)
defer func() {
require.NoError(t, os.RemoveAll(dir))
}()
opts := getTestOptions(dir)
db, err := Open(opts)
require.NoError(t, err)
sw := db.NewStreamWriter()
require.NoError(t, sw.Prepare(), "sw.Prepare() failed")
var val [10]byte
rand.Read(val[:])
buf := z.NewBuffer(10<<20, "test")
defer buf.Release()
kv1 := &pb.KV{
Key: []byte(fmt.Sprintf("%d", 1)),
Value: val[:],
Version: 1,
StreamId: uint32(1),
}
kv2 := &pb.KV{
StreamId: uint32(1),
StreamDone: true,
}
kv3 := &pb.KV{
Key: []byte(fmt.Sprintf("%d", 2)),
Value: val[:],
Version: 1,
StreamId: uint32(1),
}
KVToBuffer(kv1, buf)
KVToBuffer(kv2, buf)
KVToBuffer(kv3, buf)
// Defer for panic.
defer func() {
require.NotNil(t, recover(), "should have paniced")
require.NoError(t, sw.Flush())
require.NoError(t, db.Close())
}()
require.NoError(t, sw.Write(buf), "sw.Write() failed")
}
func TestStreamWriterEncrypted(t *testing.T) {
dir, err := ioutil.TempDir("", "badger-test")
require.NoError(t, err)
opts := DefaultOptions(dir)
defer removeDir(dir)
opts = opts.WithEncryptionKey([]byte("badgerkey16bytes"))
opts.BlockCacheSize = 100 << 20
opts.IndexCacheSize = 100 << 20
db, err := Open(opts)
require.NoError(t, err)
key := []byte("mykey")
value := []byte("myvalue")
buf := z.NewBuffer(10<<20, "test")
defer buf.Release()
KVToBuffer(&pb.KV{
Key: key,
Value: value,
Version: 20,
}, buf)
sw := db.NewStreamWriter()
require.NoError(t, sw.Prepare(), "Prepare failed")
require.NoError(t, sw.Write(buf), "Write failed")
require.NoError(t, sw.Flush(), "Flush failed")
err = db.View(func(txn *Txn) error {
item, err := txn.Get(key)
require.NoError(t, err)
val, err := item.ValueCopy(nil)
require.Equal(t, value, val)
require.NoError(t, err)
return nil
})
require.NoError(t, err, "Error while retrieving key")
require.NoError(t, db.Close())
db, err = Open(opts)
require.NoError(t, err)
require.NoError(t, db.Close())
}
// Test that stream writer does not crashes with large values in managed mode. In managed mode, we
// don't write to value log.
func TestStreamWriterWithLargeValue(t *testing.T) {
opts := DefaultOptions("")
opts.managedTxns = true
runBadgerTest(t, &opts, func(t *testing.T, db *DB) {
buf := z.NewBuffer(10<<20, "test")
defer buf.Release()
val := make([]byte, 10<<20)
_, err := rand.Read(val)
require.NoError(t, err)
KVToBuffer(&pb.KV{
Key: []byte("key"),
Value: val,
Version: 1,
}, buf)
sw := db.NewStreamWriter()
require.NoError(t, sw.Prepare(), "sw.Prepare() failed")
require.NoError(t, sw.Write(buf), "sw.Write() failed")
require.NoError(t, sw.Flush(), "sw.Flush() failed")
})
}
func TestStreamWriterIncremental(t *testing.T) {
addIncremtal := func(t *testing.T, db *DB, keys [][]byte) {
buf := z.NewBuffer(10<<20, "test")
defer buf.Release()
for _, key := range keys {
KVToBuffer(&pb.KV{
Key: key,
Value: []byte("val"),
Version: 1,
}, buf)
}
// Now do an incremental stream write.
sw := db.NewStreamWriter()
require.NoError(t, sw.PrepareIncremental(), "sw.PrepareIncremental() failed")
require.NoError(t, sw.Write(buf), "sw.Write() failed")
require.NoError(t, sw.Flush(), "sw.Flush() failed")
}
t.Run("incremental on non-empty DB", func(t *testing.T) {
runBadgerTest(t, nil, func(t *testing.T, db *DB) {
buf := z.NewBuffer(10<<20, "test")
defer buf.Release()
KVToBuffer(&pb.KV{
Key: []byte("key-1"),
Value: []byte("val"),
Version: 1,
}, buf)
sw := db.NewStreamWriter()
require.NoError(t, sw.Prepare(), "sw.Prepare() failed")
require.NoError(t, sw.Write(buf), "sw.Write() failed")
require.NoError(t, sw.Flush(), "sw.Flush() failed")
addIncremtal(t, db, [][]byte{[]byte("key-2")})
txn := db.NewTransaction(false)
defer txn.Discard()
_, err := txn.Get([]byte("key-1"))
require.NoError(t, err)
_, err = txn.Get([]byte("key-2"))
require.NoError(t, err)
})
})
t.Run("incremental on empty DB", func(t *testing.T) {
runBadgerTest(t, nil, func(t *testing.T, db *DB) {
addIncremtal(t, db, [][]byte{[]byte("key-1")})
txn := db.NewTransaction(false)
defer txn.Discard()
_, err := txn.Get([]byte("key-1"))
require.NoError(t, err)
})
})
t.Run("multiple incremental", func(t *testing.T) {
runBadgerTest(t, nil, func(t *testing.T, db *DB) {
addIncremtal(t, db, [][]byte{[]byte("a1"), []byte("c1")})
addIncremtal(t, db, [][]byte{[]byte("a2"), []byte("c2")})
addIncremtal(t, db, [][]byte{[]byte("a3"), []byte("c3")})
txn := db.NewTransaction(false)
defer txn.Discard()
_, err := txn.Get([]byte("a1"))
require.NoError(t, err)
_, err = txn.Get([]byte("c1"))
require.NoError(t, err)
_, err = txn.Get([]byte("a2"))
require.NoError(t, err)
_, err = txn.Get([]byte("c2"))
require.NoError(t, err)
_, err = txn.Get([]byte("a3"))
require.NoError(t, err)
_, err = txn.Get([]byte("c3"))
require.NoError(t, err)
})
})
}