mirror of
https://github.com/lightningnetwork/lnd.git
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c4e6f23c5b
Add a re-usable implementation of the sqldb.TxOptions interface and make use of this in the various spots (invoices, batch and graph/db) where we had previously defined individual implementations that were all doing the same thing.
695 lines
16 KiB
Go
695 lines
16 KiB
Go
package batch
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import (
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"context"
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"database/sql"
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"encoding/binary"
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"errors"
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"fmt"
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"path/filepath"
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"sync"
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"testing"
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"time"
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"github.com/btcsuite/btcwallet/walletdb"
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"github.com/lightningnetwork/lnd/kvdb"
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"github.com/lightningnetwork/lnd/sqldb"
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"github.com/lightningnetwork/lnd/sqldb/sqlc"
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"github.com/stretchr/testify/require"
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)
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// batchTestIntervals is a list of batch commit intervals to use for
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// benchmarking tests.
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var batchTestIntervals = []time.Duration{
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time.Millisecond * 0,
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time.Millisecond * 50,
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time.Millisecond * 100,
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time.Millisecond * 200,
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time.Millisecond * 500,
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}
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// TestRetry tests the retry logic of the batch scheduler.
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func TestRetry(t *testing.T) {
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t.Parallel()
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ctx := context.Background()
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dbDir := t.TempDir()
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dbName := filepath.Join(dbDir, "weks.db")
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db, err := walletdb.Create(
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"bdb", dbName, true, kvdb.DefaultDBTimeout, false,
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)
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if err != nil {
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t.Fatalf("unable to create walletdb: %v", err)
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}
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t.Cleanup(func() {
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db.Close()
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})
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var (
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mu sync.Mutex
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called int
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)
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sched := NewTimeScheduler[kvdb.RwTx](
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NewBoltBackend[kvdb.RwTx](db), &mu, time.Second,
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)
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// First, we construct a request that should retry individually and
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// execute it non-lazily. It should still return the error the second
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// time.
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req := &Request[kvdb.RwTx]{
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Do: func(tx kvdb.RwTx) error {
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called++
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return errors.New("test")
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},
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}
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err = sched.Execute(ctx, req)
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// Check and reset the called counter.
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mu.Lock()
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require.Equal(t, 2, called)
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called = 0
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mu.Unlock()
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require.ErrorContains(t, err, "test")
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// Now, we construct a request that should NOT retry because it returns
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// a serialization error, which should cause the underlying postgres
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// transaction to retry. Since we aren't using postgres, this will
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// cause the transaction to not be retried at all.
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req = &Request[kvdb.RwTx]{
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Do: func(tx kvdb.RwTx) error {
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called++
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return errors.New("could not serialize access")
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},
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}
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err = sched.Execute(ctx, req)
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// Check the called counter.
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mu.Lock()
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require.Equal(t, 1, called)
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mu.Unlock()
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require.ErrorContains(t, err, "could not serialize access")
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}
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// TestReadOnly just ensures that nothing breaks if we specify a read-only tx
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// and then continue to add a write transaction to the same batch.
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func TestReadOnly(t *testing.T) {
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t.Parallel()
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ctx := context.Background()
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t.Run("bbolt-ReadWrite", func(t *testing.T) {
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db, err := walletdb.Create(
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"bdb", filepath.Join(t.TempDir(), "weks.db"), true,
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kvdb.DefaultDBTimeout, false,
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)
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require.NoError(t, err)
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if err != nil {
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t.Fatalf("unable to create walletdb: %v", err)
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}
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t.Cleanup(func() {
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require.NoError(t, db.Close())
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})
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// Create a bbolt read-write scheduler.
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rwSche := NewTimeScheduler[kvdb.RwTx](
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NewBoltBackend[kvdb.RwTx](db), nil, time.Second,
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)
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// Call it without a read-only option.
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var called bool
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req := &Request[kvdb.RwTx]{
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Do: func(tx kvdb.RwTx) error {
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called = true
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return nil
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},
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}
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require.NoError(t, rwSche.Execute(ctx, req))
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require.True(t, called)
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// Call it with a read-only option.
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called = false
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req = &Request[kvdb.RwTx]{
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Opts: NewSchedulerOptions(ReadOnly()),
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Do: func(tx kvdb.RwTx) error {
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called = true
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return nil
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},
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}
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require.NoError(t, rwSche.Execute(ctx, req))
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require.True(t, called)
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// Now, spin off a bunch of reads and writes at the same time
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// so that we can simulate the upgrade from read-only to
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// read-write.
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var (
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wg sync.WaitGroup
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reads = 0
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readsMu sync.Mutex
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writes = 0
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writesMu sync.Mutex
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)
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for i := 0; i < 100; i++ {
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// Spin off the reads.
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wg.Add(1)
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go func() {
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defer wg.Done()
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req := &Request[kvdb.RwTx]{
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Opts: NewSchedulerOptions(ReadOnly()),
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Do: func(tx kvdb.RwTx) error {
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readsMu.Lock()
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reads++
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readsMu.Unlock()
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return nil
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},
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}
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require.NoError(t, rwSche.Execute(ctx, req))
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}()
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// Spin off the writes.
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wg.Add(1)
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go func() {
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defer wg.Done()
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req := &Request[kvdb.RwTx]{
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Do: func(tx kvdb.RwTx) error {
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writesMu.Lock()
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writes++
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writesMu.Unlock()
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return nil
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},
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}
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require.NoError(t, rwSche.Execute(ctx, req))
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}()
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}
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wg.Wait()
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require.Equal(t, 100, reads)
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require.Equal(t, 100, writes)
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})
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// Note that if the scheduler is initialized with a read-only bbolt tx,
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// then the ReadOnly option does nothing as it will be read-only
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// regardless.
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t.Run("bbolt-ReadOnly", func(t *testing.T) {
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db, err := walletdb.Create(
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"bdb", filepath.Join(t.TempDir(), "weks.db"), true,
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kvdb.DefaultDBTimeout, false,
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)
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require.NoError(t, err)
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if err != nil {
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t.Fatalf("unable to create walletdb: %v", err)
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}
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t.Cleanup(func() {
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require.NoError(t, db.Close())
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})
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// Create a bbolt read only scheduler.
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rwSche := NewTimeScheduler[kvdb.RTx](
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NewBoltBackend[kvdb.RTx](db), nil, time.Second,
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)
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// Call it without a read-only option.
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var called bool
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req := &Request[kvdb.RTx]{
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Do: func(tx kvdb.RTx) error {
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called = true
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return nil
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},
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}
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require.NoError(t, rwSche.Execute(ctx, req))
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require.True(t, called)
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// Call it with a read-only option.
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called = false
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req = &Request[kvdb.RTx]{
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Opts: NewSchedulerOptions(ReadOnly()),
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Do: func(tx kvdb.RTx) error {
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called = true
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return nil
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},
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}
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require.NoError(t, rwSche.Execute(ctx, req))
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require.True(t, called)
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})
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t.Run("sql", func(t *testing.T) {
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base := sqldb.NewTestSqliteDB(t).BaseDB
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db := sqldb.NewTransactionExecutor(
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base, func(tx *sql.Tx) *sqlc.Queries {
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return base.WithTx(tx)
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},
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)
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// Create a SQL scheduler with a long batch interval.
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scheduler := NewTimeScheduler[*sqlc.Queries](
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db, nil, time.Second,
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)
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// writeRecord is a helper that adds a single new invoice to the
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// database. It uses the 'i' argument to create a unique hash
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// for the invoice.
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writeRecord := func(t *testing.T, tx *sqlc.Queries, i int64) {
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var hash [8]byte
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binary.BigEndian.PutUint64(hash[:], uint64(i))
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_, err := tx.InsertInvoice(
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ctx, sqlc.InsertInvoiceParams{
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Hash: hash[:],
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PaymentAddr: hash[:],
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PaymentRequestHash: hash[:],
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Expiry: -123,
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},
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)
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require.NoError(t, err)
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}
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// readRecord is a helper that reads a single invoice from the
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// database. It uses the 'i' argument to create a unique hash
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// for the invoice.
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readRecord := func(t *testing.T, tx *sqlc.Queries,
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i int) error {
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var hash [8]byte
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binary.BigEndian.PutUint64(hash[:], uint64(i))
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_, err := tx.GetInvoiceByHash(ctx, hash[:])
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return err
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}
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// Execute a bunch of read-only requests in parallel. These
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// should be batched together and kept as read only.
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var wg sync.WaitGroup
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for i := 0; i < 100; i++ {
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wg.Add(1)
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go func(i int) {
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defer wg.Done()
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req := &Request[*sqlc.Queries]{
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Opts: NewSchedulerOptions(ReadOnly()),
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Do: func(tx *sqlc.Queries) error {
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err := readRecord(t, tx, i)
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require.ErrorIs(
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t, err, sql.ErrNoRows,
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)
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return nil
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},
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}
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require.NoError(t, scheduler.Execute(ctx, req))
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}(i)
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}
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wg.Wait()
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// Now, execute reads and writes in parallel. These should be
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// batched together and the tx should be updated to read-write.
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// We just simulate this scenario. Write transactions succeeding
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// are how we know that the tx was upgraded to read-write.
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for i := 0; i < 100; i++ {
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// Spin off the writes.
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wg.Add(1)
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go func(i int) {
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defer wg.Done()
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req := &Request[*sqlc.Queries]{
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Do: func(tx *sqlc.Queries) error {
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writeRecord(t, tx, int64(i))
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return nil
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},
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}
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require.NoError(t, scheduler.Execute(ctx, req))
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}(i)
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// Spin off the reads.
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wg.Add(1)
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go func(i int) {
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defer wg.Done()
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errExpected := func(err error) {
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noRows := errors.Is(err, sql.ErrNoRows)
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require.True(t, err == nil || noRows)
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}
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req := &Request[*sqlc.Queries]{
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Opts: NewSchedulerOptions(ReadOnly()),
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Do: func(tx *sqlc.Queries) error {
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err := readRecord(t, tx, i)
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errExpected(err)
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return nil
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},
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}
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require.NoError(t, scheduler.Execute(ctx, req))
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}(i)
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}
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wg.Wait()
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})
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}
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// BenchmarkBoltBatching benchmarks the performance of the batch scheduler
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// against the bolt backend.
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func BenchmarkBoltBatching(b *testing.B) {
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setUpDB := func(b *testing.B) kvdb.Backend {
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// Create a new database backend for the test.
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backend, backendCleanup, err := kvdb.GetTestBackend(
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b.TempDir(), "db",
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)
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require.NoError(b, err)
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b.Cleanup(func() { backendCleanup() })
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return backend
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}
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// writeRecord is a helper that writes a simple record to the
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// database. It creates a top-level bucket and a sub-bucket, then
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// writes a record with a sequence number as the key.
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writeRecord := func(b *testing.B, tx kvdb.RwTx) {
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bucket, err := tx.CreateTopLevelBucket([]byte("top-level"))
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require.NoError(b, err)
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subBucket, err := bucket.CreateBucketIfNotExists(
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[]byte("sub-bucket"),
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)
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require.NoError(b, err)
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seq, err := subBucket.NextSequence()
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require.NoError(b, err)
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var key [8]byte
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binary.BigEndian.PutUint64(key[:], seq)
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err = subBucket.Put(key[:], []byte("value"))
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require.NoError(b, err)
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}
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// verifyRecordsWritten is a helper that verifies that the writeRecord
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// helper was called the expected number of times.
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verifyRecordsWritten := func(b *testing.B, db kvdb.Backend, N int) {
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err := db.View(func(tx kvdb.RTx) error {
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bucket := tx.ReadBucket([]byte("top-level"))
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require.NotNil(b, bucket)
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subBucket := bucket.NestedReadBucket(
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[]byte("sub-bucket"),
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)
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require.NotNil(b, subBucket)
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require.EqualValues(b, subBucket.Sequence(), N)
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return nil
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}, func() {})
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require.NoError(b, err)
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}
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// This test benchmarks the performance when using N new transactions
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// for N write queries. This does not use the scheduler.
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b.Run("N txs for N write queries", func(b *testing.B) {
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db := setUpDB(b)
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b.ResetTimer()
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var wg sync.WaitGroup
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for i := 0; i < b.N; i++ {
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wg.Add(1)
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go func() {
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defer wg.Done()
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err := db.Update(func(tx kvdb.RwTx) error {
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writeRecord(b, tx)
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return nil
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}, func() {})
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require.NoError(b, err)
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}()
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}
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wg.Wait()
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b.StopTimer()
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verifyRecordsWritten(b, db, b.N)
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})
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// This test benchmarks the performance when using a single transaction
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// for N write queries. This does not use the scheduler.
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b.Run("1 txs for N write queries", func(b *testing.B) {
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db := setUpDB(b)
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b.ResetTimer()
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err := db.Update(func(tx kvdb.RwTx) error {
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for i := 0; i < b.N; i++ {
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writeRecord(b, tx)
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}
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return nil
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}, func() {})
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require.NoError(b, err)
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b.StopTimer()
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verifyRecordsWritten(b, db, b.N)
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})
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// batchTest benches the performance of the batch scheduler configured
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// with/without the LazyAdd option and with the given commit interval.
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batchTest := func(b *testing.B, lazy bool, interval time.Duration) {
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ctx := context.Background()
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db := setUpDB(b)
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scheduler := NewTimeScheduler(
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NewBoltBackend[kvdb.RwTx](db), nil, interval,
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)
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var opts []SchedulerOption
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if lazy {
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opts = append(opts, LazyAdd())
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}
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b.ResetTimer()
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var wg sync.WaitGroup
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for i := 0; i < b.N; i++ {
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wg.Add(1)
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go func() {
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defer wg.Done()
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r := &Request[kvdb.RwTx]{
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Opts: NewSchedulerOptions(
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opts...,
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),
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Do: func(tx kvdb.RwTx) error {
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writeRecord(b, tx)
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return nil
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},
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}
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err := scheduler.Execute(ctx, r)
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require.NoError(b, err)
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}()
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}
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wg.Wait()
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b.StopTimer()
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verifyRecordsWritten(b, db, b.N)
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}
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for _, lazy := range []bool{true, false} {
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for _, interval := range batchTestIntervals {
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name := fmt.Sprintf(
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"batched queries %s lazy: %v", interval, lazy,
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)
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b.Run(name, func(b *testing.B) {
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batchTest(b, lazy, interval)
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})
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}
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}
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}
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// BenchmarkSQLBatching benchmarks the performance of the batch scheduler
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// against the sqlite and postgres backends.
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func BenchmarkSQLBatching(b *testing.B) {
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b.Run("sqlite", func(b *testing.B) {
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benchmarkSQLBatching(b, true)
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})
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b.Run("postgres", func(b *testing.B) {
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benchmarkSQLBatching(b, false)
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})
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}
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// benchmarkSQLBatching benchmarks the performance of the batch scheduler
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// against an SQL backend. It uses the AddInvoice query as the operation to
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// benchmark.
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func benchmarkSQLBatching(b *testing.B, sqlite bool) {
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// First create a shared Postgres instance so we don't spawn a new
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// docker container for each test.
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pgFixture := sqldb.NewTestPgFixture(
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b, sqldb.DefaultPostgresFixtureLifetime,
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)
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b.Cleanup(func() {
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pgFixture.TearDown(b)
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})
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setUpDB := func(b *testing.B) sqldb.BatchedTx[*sqlc.Queries] {
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var db *sqldb.BaseDB
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if sqlite {
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db = sqldb.NewTestSqliteDB(b).BaseDB
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} else {
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db = sqldb.NewTestPostgresDB(b, pgFixture).BaseDB
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}
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return sqldb.NewTransactionExecutor(
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db, func(tx *sql.Tx) *sqlc.Queries {
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return db.WithTx(tx)
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},
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)
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}
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ctx := context.Background()
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opts := sqldb.WriteTxOpt()
|
|
|
|
// writeRecord is a helper that adds a single new invoice to the
|
|
// database. It uses the 'i' argument to create a unique hash for the
|
|
// invoice.
|
|
writeRecord := func(b *testing.B, tx *sqlc.Queries, i int64) {
|
|
var hash [8]byte
|
|
binary.BigEndian.PutUint64(hash[:], uint64(i))
|
|
|
|
_, err := tx.InsertInvoice(ctx, sqlc.InsertInvoiceParams{
|
|
Hash: hash[:],
|
|
PaymentAddr: hash[:],
|
|
PaymentRequestHash: hash[:],
|
|
Expiry: -123,
|
|
})
|
|
require.NoError(b, err)
|
|
}
|
|
|
|
// verifyRecordsWritten is a helper that verifies that the writeRecord
|
|
// helper was called the expected number of times. We know that N was
|
|
// used to derive the hash for each invoice persisted to the DB, so we
|
|
// can use it to verify that the last expected invoice was written.
|
|
verifyRecordsWritten := func(b *testing.B,
|
|
tx sqldb.BatchedTx[*sqlc.Queries], N int) {
|
|
|
|
var hash [8]byte
|
|
binary.BigEndian.PutUint64(hash[:], uint64(N-1))
|
|
|
|
err := tx.ExecTx(ctx, opts, func(queries *sqlc.Queries) error {
|
|
_, err := queries.GetInvoiceByHash(ctx, hash[:])
|
|
require.NoError(b, err)
|
|
|
|
return nil
|
|
}, func() {},
|
|
)
|
|
require.NoError(b, err)
|
|
}
|
|
|
|
// This test benchmarks the performance when using N new transactions
|
|
// for N write queries. This does not use the scheduler.
|
|
b.Run("N txs for N write queries", func(b *testing.B) {
|
|
db := setUpDB(b)
|
|
b.ResetTimer()
|
|
|
|
var wg sync.WaitGroup
|
|
for i := 0; i < b.N; i++ {
|
|
wg.Add(1)
|
|
go func(j int) {
|
|
defer wg.Done()
|
|
|
|
err := db.ExecTx(
|
|
ctx, opts,
|
|
func(tx *sqlc.Queries) error {
|
|
writeRecord(b, tx, int64(j))
|
|
return nil
|
|
}, func() {},
|
|
)
|
|
require.NoError(b, err)
|
|
}(i)
|
|
}
|
|
wg.Wait()
|
|
|
|
b.StopTimer()
|
|
verifyRecordsWritten(b, db, b.N)
|
|
})
|
|
|
|
// This test benchmarks the performance when using a single transaction
|
|
// for N write queries. This does not use the scheduler.
|
|
b.Run("1 txs for N write queries", func(b *testing.B) {
|
|
db := setUpDB(b)
|
|
b.ResetTimer()
|
|
|
|
err := db.ExecTx(
|
|
ctx, opts,
|
|
func(tx *sqlc.Queries) error {
|
|
for i := 0; i < b.N; i++ {
|
|
writeRecord(b, tx, int64(i))
|
|
}
|
|
|
|
return nil
|
|
}, func() {},
|
|
)
|
|
require.NoError(b, err)
|
|
|
|
b.StopTimer()
|
|
verifyRecordsWritten(b, db, b.N)
|
|
})
|
|
|
|
// batchTest benches the performance of the batch scheduler configured
|
|
// with/without the LazyAdd option and with the given commit interval.
|
|
batchTest := func(b *testing.B, lazy bool, interval time.Duration) {
|
|
db := setUpDB(b)
|
|
|
|
scheduler := NewTimeScheduler[*sqlc.Queries](
|
|
db, nil, interval,
|
|
)
|
|
|
|
var opts []SchedulerOption
|
|
if lazy {
|
|
opts = append(opts, LazyAdd())
|
|
}
|
|
|
|
b.ResetTimer()
|
|
|
|
var wg sync.WaitGroup
|
|
for i := 0; i < b.N; i++ {
|
|
wg.Add(1)
|
|
go func(j int) {
|
|
defer wg.Done()
|
|
|
|
r := &Request[*sqlc.Queries]{
|
|
Opts: NewSchedulerOptions(
|
|
opts...,
|
|
),
|
|
Do: func(tx *sqlc.Queries) error {
|
|
writeRecord(b, tx, int64(j))
|
|
return nil
|
|
},
|
|
}
|
|
|
|
err := scheduler.Execute(ctx, r)
|
|
require.NoError(b, err)
|
|
}(i)
|
|
}
|
|
wg.Wait()
|
|
|
|
b.StopTimer()
|
|
verifyRecordsWritten(b, db, b.N)
|
|
}
|
|
|
|
for _, lazy := range []bool{true, false} {
|
|
for _, interval := range batchTestIntervals {
|
|
name := fmt.Sprintf(
|
|
"batched queries %s lazy: %v", interval, lazy,
|
|
)
|
|
|
|
b.Run(name, func(b *testing.B) {
|
|
batchTest(b, lazy, interval)
|
|
})
|
|
}
|
|
}
|
|
}
|