bsc/core/blockchain_snapshot_test.go
gary rong b63e3c37a6
core: improve snapshot journal recovery (#21594)
* core/state/snapshot: introduce snapshot journal version

* core: update the disk layer in an atomic way

* core: persist the disk layer generator periodically

* core/state/snapshot: improve logging

* core/state/snapshot: forcibly ensure the legacy snapshot is matched

* core/state/snapshot: add debug logs

* core, tests: fix tests and special recovery case

* core: polish

* core: add more blockchain tests for snapshot recovery

* core/state: fix comment

* core: add recovery flag for snapshot

* core: add restart after start-after-crash tests

* core/rawdb: fix imports

* core: fix tests

* core: remove log

* core/state/snapshot: fix snapshot

* core: avoid callbacks in SetHead

* core: fix setHead cornercase where the threshold root has state

* core: small docs for the test cases

Co-authored-by: Péter Szilágyi <peterke@gmail.com>
2020-10-29 21:01:58 +02:00

733 lines
23 KiB
Go

// Copyright 2020 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
// Tests that abnormal program termination (i.e.crash) and restart can recovery
// the snapshot properly if the snapshot is enabled.
package core
import (
"bytes"
"fmt"
"io/ioutil"
"os"
"strings"
"testing"
"time"
"github.com/ethereum/go-ethereum/consensus/ethash"
"github.com/ethereum/go-ethereum/core/rawdb"
"github.com/ethereum/go-ethereum/core/vm"
"github.com/ethereum/go-ethereum/params"
)
// snapshotTest is a test case for snapshot recovery. It can be used for
// simulating these scenarios:
// (i) Geth restarts normally with valid legacy snapshot
// (ii) Geth restarts normally with valid new-format snapshot
// (iii) Geth restarts after the crash, with broken legacy snapshot
// (iv) Geth restarts after the crash, with broken new-format snapshot
// (v) Geth restarts normally, but it's requested to be rewound to a lower point via SetHead
// (vi) Geth restarts normally with a stale snapshot
type snapshotTest struct {
legacy bool // Flag whether the loaded snapshot is in legacy format
crash bool // Flag whether the Geth restarts from the previous crash
gapped int // Number of blocks to insert without enabling snapshot
setHead uint64 // Block number to set head back to
chainBlocks int // Number of blocks to generate for the canonical chain
snapshotBlock uint64 // Block number of the relevant snapshot disk layer
commitBlock uint64 // Block number for which to commit the state to disk
expCanonicalBlocks int // Number of canonical blocks expected to remain in the database (excl. genesis)
expHeadHeader uint64 // Block number of the expected head header
expHeadFastBlock uint64 // Block number of the expected head fast sync block
expHeadBlock uint64 // Block number of the expected head full block
expSnapshotBottom uint64 // The block height corresponding to the snapshot disk layer
}
func (tt *snapshotTest) dump() string {
buffer := new(strings.Builder)
fmt.Fprint(buffer, "Chain:\n G")
for i := 0; i < tt.chainBlocks; i++ {
fmt.Fprintf(buffer, "->C%d", i+1)
}
fmt.Fprint(buffer, " (HEAD)\n\n")
fmt.Fprintf(buffer, "Commit: G")
if tt.commitBlock > 0 {
fmt.Fprintf(buffer, ", C%d", tt.commitBlock)
}
fmt.Fprint(buffer, "\n")
fmt.Fprintf(buffer, "Snapshot: G")
if tt.snapshotBlock > 0 {
fmt.Fprintf(buffer, ", C%d", tt.snapshotBlock)
}
fmt.Fprint(buffer, "\n")
if tt.crash {
fmt.Fprintf(buffer, "\nCRASH\n\n")
} else {
fmt.Fprintf(buffer, "\nSetHead(%d)\n\n", tt.setHead)
}
fmt.Fprintf(buffer, "------------------------------\n\n")
fmt.Fprint(buffer, "Expected in leveldb:\n G")
for i := 0; i < tt.expCanonicalBlocks; i++ {
fmt.Fprintf(buffer, "->C%d", i+1)
}
fmt.Fprintf(buffer, "\n\n")
fmt.Fprintf(buffer, "Expected head header : C%d\n", tt.expHeadHeader)
fmt.Fprintf(buffer, "Expected head fast block: C%d\n", tt.expHeadFastBlock)
if tt.expHeadBlock == 0 {
fmt.Fprintf(buffer, "Expected head block : G\n")
} else {
fmt.Fprintf(buffer, "Expected head block : C%d\n", tt.expHeadBlock)
}
if tt.expSnapshotBottom == 0 {
fmt.Fprintf(buffer, "Expected snapshot disk : G\n")
} else {
fmt.Fprintf(buffer, "Expected snapshot disk : C%d\n", tt.expSnapshotBottom)
}
return buffer.String()
}
// Tests a Geth restart with valid snapshot. Before the shutdown, all snapshot
// journal will be persisted correctly. In this case no snapshot recovery is
// required.
func TestRestartWithNewSnapshot(t *testing.T) {
// Chain:
// G->C1->C2->C3->C4->C5->C6->C7->C8 (HEAD)
//
// Commit: G
// Snapshot: G
//
// SetHead(0)
//
// ------------------------------
//
// Expected in leveldb:
// G->C1->C2->C3->C4->C5->C6->C7->C8
//
// Expected head header : C8
// Expected head fast block: C8
// Expected head block : C8
// Expected snapshot disk : G
testSnapshot(t, &snapshotTest{
legacy: false,
crash: false,
gapped: 0,
setHead: 0,
chainBlocks: 8,
snapshotBlock: 0,
commitBlock: 0,
expCanonicalBlocks: 8,
expHeadHeader: 8,
expHeadFastBlock: 8,
expHeadBlock: 8,
expSnapshotBottom: 0, // Initial disk layer built from genesis
})
}
// Tests a Geth restart with valid but "legacy" snapshot. Before the shutdown,
// all snapshot journal will be persisted correctly. In this case no snapshot
// recovery is required.
func TestRestartWithLegacySnapshot(t *testing.T) {
// Chain:
// G->C1->C2->C3->C4->C5->C6->C7->C8 (HEAD)
//
// Commit: G
// Snapshot: G
//
// SetHead(0)
//
// ------------------------------
//
// Expected in leveldb:
// G->C1->C2->C3->C4->C5->C6->C7->C8
//
// Expected head header : C8
// Expected head fast block: C8
// Expected head block : C8
// Expected snapshot disk : G
testSnapshot(t, &snapshotTest{
legacy: true,
crash: false,
gapped: 0,
setHead: 0,
chainBlocks: 8,
snapshotBlock: 0,
commitBlock: 0,
expCanonicalBlocks: 8,
expHeadHeader: 8,
expHeadFastBlock: 8,
expHeadBlock: 8,
expSnapshotBottom: 0, // Initial disk layer built from genesis
})
}
// Tests a Geth was crashed and restarts with a broken snapshot. In this case the
// chain head should be rewound to the point with available state. And also the
// new head should must be lower than disk layer. But there is no committed point
// so the chain should be rewound to genesis and the disk layer should be left
// for recovery.
func TestNoCommitCrashWithNewSnapshot(t *testing.T) {
// Chain:
// G->C1->C2->C3->C4->C5->C6->C7->C8 (HEAD)
//
// Commit: G
// Snapshot: G, C4
//
// CRASH
//
// ------------------------------
//
// Expected in leveldb:
// G->C1->C2->C3->C4->C5->C6->C7->C8
//
// Expected head header : C8
// Expected head fast block: C8
// Expected head block : G
// Expected snapshot disk : C4
testSnapshot(t, &snapshotTest{
legacy: false,
crash: true,
gapped: 0,
setHead: 0,
chainBlocks: 8,
snapshotBlock: 4,
commitBlock: 0,
expCanonicalBlocks: 8,
expHeadHeader: 8,
expHeadFastBlock: 8,
expHeadBlock: 0,
expSnapshotBottom: 4, // Last committed disk layer, wait recovery
})
}
// Tests a Geth was crashed and restarts with a broken snapshot. In this case the
// chain head should be rewound to the point with available state. And also the
// new head should must be lower than disk layer. But there is only a low committed
// point so the chain should be rewound to committed point and the disk layer
// should be left for recovery.
func TestLowCommitCrashWithNewSnapshot(t *testing.T) {
// Chain:
// G->C1->C2->C3->C4->C5->C6->C7->C8 (HEAD)
//
// Commit: G, C2
// Snapshot: G, C4
//
// CRASH
//
// ------------------------------
//
// Expected in leveldb:
// G->C1->C2->C3->C4->C5->C6->C7->C8
//
// Expected head header : C8
// Expected head fast block: C8
// Expected head block : C2
// Expected snapshot disk : C4
testSnapshot(t, &snapshotTest{
legacy: false,
crash: true,
gapped: 0,
setHead: 0,
chainBlocks: 8,
snapshotBlock: 4,
commitBlock: 2,
expCanonicalBlocks: 8,
expHeadHeader: 8,
expHeadFastBlock: 8,
expHeadBlock: 2,
expSnapshotBottom: 4, // Last committed disk layer, wait recovery
})
}
// Tests a Geth was crashed and restarts with a broken snapshot. In this case
// the chain head should be rewound to the point with available state. And also
// the new head should must be lower than disk layer. But there is only a high
// committed point so the chain should be rewound to genesis and the disk layer
// should be left for recovery.
func TestHighCommitCrashWithNewSnapshot(t *testing.T) {
// Chain:
// G->C1->C2->C3->C4->C5->C6->C7->C8 (HEAD)
//
// Commit: G, C6
// Snapshot: G, C4
//
// CRASH
//
// ------------------------------
//
// Expected in leveldb:
// G->C1->C2->C3->C4->C5->C6->C7->C8
//
// Expected head header : C8
// Expected head fast block: C8
// Expected head block : G
// Expected snapshot disk : C4
testSnapshot(t, &snapshotTest{
legacy: false,
crash: true,
gapped: 0,
setHead: 0,
chainBlocks: 8,
snapshotBlock: 4,
commitBlock: 6,
expCanonicalBlocks: 8,
expHeadHeader: 8,
expHeadFastBlock: 8,
expHeadBlock: 0,
expSnapshotBottom: 4, // Last committed disk layer, wait recovery
})
}
// Tests a Geth was crashed and restarts with a broken and "legacy format"
// snapshot. In this case the entire legacy snapshot should be discared
// and rebuild from the new chain head. The new head here refers to the
// genesis because there is no committed point.
func TestNoCommitCrashWithLegacySnapshot(t *testing.T) {
// Chain:
// G->C1->C2->C3->C4->C5->C6->C7->C8 (HEAD)
//
// Commit: G
// Snapshot: G, C4
//
// CRASH
//
// ------------------------------
//
// Expected in leveldb:
// G->C1->C2->C3->C4->C5->C6->C7->C8
//
// Expected head header : C8
// Expected head fast block: C8
// Expected head block : G
// Expected snapshot disk : G
testSnapshot(t, &snapshotTest{
legacy: true,
crash: true,
gapped: 0,
setHead: 0,
chainBlocks: 8,
snapshotBlock: 4,
commitBlock: 0,
expCanonicalBlocks: 8,
expHeadHeader: 8,
expHeadFastBlock: 8,
expHeadBlock: 0,
expSnapshotBottom: 0, // Rebuilt snapshot from the latest HEAD(genesis)
})
}
// Tests a Geth was crashed and restarts with a broken and "legacy format"
// snapshot. In this case the entire legacy snapshot should be discared
// and rebuild from the new chain head. The new head here refers to the
// block-2 because it's committed into the disk.
func TestLowCommitCrashWithLegacySnapshot(t *testing.T) {
// Chain:
// G->C1->C2->C3->C4->C5->C6->C7->C8 (HEAD)
//
// Commit: G, C2
// Snapshot: G, C4
//
// CRASH
//
// ------------------------------
//
// Expected in leveldb:
// G->C1->C2->C3->C4->C5->C6->C7->C8
//
// Expected head header : C8
// Expected head fast block: C8
// Expected head block : C2
// Expected snapshot disk : C2
testSnapshot(t, &snapshotTest{
legacy: true,
crash: true,
gapped: 0,
setHead: 0,
chainBlocks: 8,
snapshotBlock: 4,
commitBlock: 2,
expCanonicalBlocks: 8,
expHeadHeader: 8,
expHeadFastBlock: 8,
expHeadBlock: 2,
expSnapshotBottom: 2, // Rebuilt snapshot from the latest HEAD
})
}
// Tests a Geth was crashed and restarts with a broken and "legacy format"
// snapshot. In this case the entire legacy snapshot should be discared
// and rebuild from the new chain head.
//
// The new head here refers to the the genesis, the reason is:
// - the state of block-6 is committed into the disk
// - the legacy disk layer of block-4 is committed into the disk
// - the head is rewound the genesis in order to find an available
// state lower than disk layer
func TestHighCommitCrashWithLegacySnapshot(t *testing.T) {
// Chain:
// G->C1->C2->C3->C4->C5->C6->C7->C8 (HEAD)
//
// Commit: G, C6
// Snapshot: G, C4
//
// CRASH
//
// ------------------------------
//
// Expected in leveldb:
// G->C1->C2->C3->C4->C5->C6->C7->C8
//
// Expected head header : C8
// Expected head fast block: C8
// Expected head block : G
// Expected snapshot disk : G
testSnapshot(t, &snapshotTest{
legacy: true,
crash: true,
gapped: 0,
setHead: 0,
chainBlocks: 8,
snapshotBlock: 4,
commitBlock: 6,
expCanonicalBlocks: 8,
expHeadHeader: 8,
expHeadFastBlock: 8,
expHeadBlock: 0,
expSnapshotBottom: 0, // Rebuilt snapshot from the latest HEAD(genesis)
})
}
// Tests a Geth was running with snapshot enabled. Then restarts without
// enabling snapshot and after that re-enable the snapshot again. In this
// case the snapshot should be rebuilt with latest chain head.
func TestGappedNewSnapshot(t *testing.T) {
// Chain:
// G->C1->C2->C3->C4->C5->C6->C7->C8 (HEAD)
//
// Commit: G
// Snapshot: G
//
// SetHead(0)
//
// ------------------------------
//
// Expected in leveldb:
// G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10
//
// Expected head header : C10
// Expected head fast block: C10
// Expected head block : C10
// Expected snapshot disk : C10
testSnapshot(t, &snapshotTest{
legacy: false,
crash: false,
gapped: 2,
setHead: 0,
chainBlocks: 8,
snapshotBlock: 0,
commitBlock: 0,
expCanonicalBlocks: 10,
expHeadHeader: 10,
expHeadFastBlock: 10,
expHeadBlock: 10,
expSnapshotBottom: 10, // Rebuilt snapshot from the latest HEAD
})
}
// Tests a Geth was running with leagcy snapshot enabled. Then restarts
// without enabling snapshot and after that re-enable the snapshot again.
// In this case the snapshot should be rebuilt with latest chain head.
func TestGappedLegacySnapshot(t *testing.T) {
// Chain:
// G->C1->C2->C3->C4->C5->C6->C7->C8 (HEAD)
//
// Commit: G
// Snapshot: G
//
// SetHead(0)
//
// ------------------------------
//
// Expected in leveldb:
// G->C1->C2->C3->C4->C5->C6->C7->C8->C9->C10
//
// Expected head header : C10
// Expected head fast block: C10
// Expected head block : C10
// Expected snapshot disk : C10
testSnapshot(t, &snapshotTest{
legacy: true,
crash: false,
gapped: 2,
setHead: 0,
chainBlocks: 8,
snapshotBlock: 0,
commitBlock: 0,
expCanonicalBlocks: 10,
expHeadHeader: 10,
expHeadFastBlock: 10,
expHeadBlock: 10,
expSnapshotBottom: 10, // Rebuilt snapshot from the latest HEAD
})
}
// Tests the Geth was running with snapshot enabled and resetHead is applied.
// In this case the head is rewound to the target(with state available). After
// that the chain is restarted and the original disk layer is kept.
func TestSetHeadWithNewSnapshot(t *testing.T) {
// Chain:
// G->C1->C2->C3->C4->C5->C6->C7->C8 (HEAD)
//
// Commit: G
// Snapshot: G
//
// SetHead(4)
//
// ------------------------------
//
// Expected in leveldb:
// G->C1->C2->C3->C4
//
// Expected head header : C4
// Expected head fast block: C4
// Expected head block : C4
// Expected snapshot disk : G
testSnapshot(t, &snapshotTest{
legacy: false,
crash: false,
gapped: 0,
setHead: 4,
chainBlocks: 8,
snapshotBlock: 0,
commitBlock: 0,
expCanonicalBlocks: 4,
expHeadHeader: 4,
expHeadFastBlock: 4,
expHeadBlock: 4,
expSnapshotBottom: 0, // The initial disk layer is built from the genesis
})
}
// Tests the Geth was running with snapshot(legacy-format) enabled and resetHead
// is applied. In this case the head is rewound to the target(with state available).
// After that the chain is restarted and the original disk layer is kept.
func TestSetHeadWithLegacySnapshot(t *testing.T) {
// Chain:
// G->C1->C2->C3->C4->C5->C6->C7->C8 (HEAD)
//
// Commit: G
// Snapshot: G
//
// SetHead(4)
//
// ------------------------------
//
// Expected in leveldb:
// G->C1->C2->C3->C4
//
// Expected head header : C4
// Expected head fast block: C4
// Expected head block : C4
// Expected snapshot disk : G
testSnapshot(t, &snapshotTest{
legacy: true,
crash: false,
gapped: 0,
setHead: 4,
chainBlocks: 8,
snapshotBlock: 0,
commitBlock: 0,
expCanonicalBlocks: 4,
expHeadHeader: 4,
expHeadFastBlock: 4,
expHeadBlock: 4,
expSnapshotBottom: 0, // The initial disk layer is built from the genesis
})
}
func testSnapshot(t *testing.T, tt *snapshotTest) {
// It's hard to follow the test case, visualize the input
//log.Root().SetHandler(log.LvlFilterHandler(log.LvlTrace, log.StreamHandler(os.Stderr, log.TerminalFormat(true))))
//fmt.Println(tt.dump())
// Create a temporary persistent database
datadir, err := ioutil.TempDir("", "")
if err != nil {
t.Fatalf("Failed to create temporary datadir: %v", err)
}
os.RemoveAll(datadir)
db, err := rawdb.NewLevelDBDatabaseWithFreezer(datadir, 0, 0, datadir, "")
if err != nil {
t.Fatalf("Failed to create persistent database: %v", err)
}
defer db.Close() // Might double close, should be fine
// Initialize a fresh chain
var (
genesis = new(Genesis).MustCommit(db)
engine = ethash.NewFullFaker()
gendb = rawdb.NewMemoryDatabase()
// Snapshot is enabled, the first snapshot is created from the Genesis.
// The snapshot memory allowance is 256MB, it means no snapshot flush
// will happen during the block insertion.
cacheConfig = defaultCacheConfig
)
chain, err := NewBlockChain(db, cacheConfig, params.AllEthashProtocolChanges, engine, vm.Config{}, nil, nil)
if err != nil {
t.Fatalf("Failed to create chain: %v", err)
}
blocks, _ := GenerateChain(params.TestChainConfig, genesis, engine, gendb, tt.chainBlocks, func(i int, b *BlockGen) {})
// Insert the blocks with configured settings.
var breakpoints []uint64
if tt.commitBlock > tt.snapshotBlock {
breakpoints = append(breakpoints, tt.snapshotBlock, tt.commitBlock)
} else {
breakpoints = append(breakpoints, tt.commitBlock, tt.snapshotBlock)
}
var startPoint uint64
for _, point := range breakpoints {
if _, err := chain.InsertChain(blocks[startPoint:point]); err != nil {
t.Fatalf("Failed to import canonical chain start: %v", err)
}
startPoint = point
if tt.commitBlock > 0 && tt.commitBlock == point {
chain.stateCache.TrieDB().Commit(blocks[point-1].Root(), true, nil)
}
if tt.snapshotBlock > 0 && tt.snapshotBlock == point {
if tt.legacy {
// Here we commit the snapshot disk root to simulate
// committing the legacy snapshot.
rawdb.WriteSnapshotRoot(db, blocks[point-1].Root())
} else {
chain.snaps.Cap(blocks[point-1].Root(), 0)
diskRoot, blockRoot := chain.snaps.DiskRoot(), blocks[point-1].Root()
if !bytes.Equal(diskRoot.Bytes(), blockRoot.Bytes()) {
t.Fatalf("Failed to flush disk layer change, want %x, got %x", blockRoot, diskRoot)
}
}
}
}
if _, err := chain.InsertChain(blocks[startPoint:]); err != nil {
t.Fatalf("Failed to import canonical chain tail: %v", err)
}
// Set the flag for writing legacy journal if ncessary
if tt.legacy {
chain.writeLegacyJournal = true
}
// Pull the plug on the database, simulating a hard crash
if tt.crash {
db.Close()
// Start a new blockchain back up and see where the repair leads us
db, err = rawdb.NewLevelDBDatabaseWithFreezer(datadir, 0, 0, datadir, "")
if err != nil {
t.Fatalf("Failed to reopen persistent database: %v", err)
}
defer db.Close()
// The interesting thing is: instead of start the blockchain after
// the crash, we do restart twice here: one after the crash and one
// after the normal stop. It's used to ensure the broken snapshot
// can be detected all the time.
chain, err = NewBlockChain(db, nil, params.AllEthashProtocolChanges, engine, vm.Config{}, nil, nil)
if err != nil {
t.Fatalf("Failed to recreate chain: %v", err)
}
chain.Stop()
chain, err = NewBlockChain(db, nil, params.AllEthashProtocolChanges, engine, vm.Config{}, nil, nil)
if err != nil {
t.Fatalf("Failed to recreate chain: %v", err)
}
defer chain.Stop()
} else if tt.gapped > 0 {
// Insert blocks without enabling snapshot if gapping is required.
chain.Stop()
gappedBlocks, _ := GenerateChain(params.TestChainConfig, blocks[len(blocks)-1], engine, gendb, tt.gapped, func(i int, b *BlockGen) {})
// Insert a few more blocks without enabling snapshot
var cacheConfig = &CacheConfig{
TrieCleanLimit: 256,
TrieDirtyLimit: 256,
TrieTimeLimit: 5 * time.Minute,
SnapshotLimit: 0,
}
chain, err = NewBlockChain(db, cacheConfig, params.AllEthashProtocolChanges, engine, vm.Config{}, nil, nil)
if err != nil {
t.Fatalf("Failed to recreate chain: %v", err)
}
chain.InsertChain(gappedBlocks)
chain.Stop()
chain, err = NewBlockChain(db, nil, params.AllEthashProtocolChanges, engine, vm.Config{}, nil, nil)
if err != nil {
t.Fatalf("Failed to recreate chain: %v", err)
}
defer chain.Stop()
} else if tt.setHead != 0 {
// Rewind the chain if setHead operation is required.
chain.SetHead(tt.setHead)
chain.Stop()
chain, err = NewBlockChain(db, nil, params.AllEthashProtocolChanges, engine, vm.Config{}, nil, nil)
if err != nil {
t.Fatalf("Failed to recreate chain: %v", err)
}
defer chain.Stop()
} else {
chain.Stop()
// Restart the chain normally
chain, err = NewBlockChain(db, nil, params.AllEthashProtocolChanges, engine, vm.Config{}, nil, nil)
if err != nil {
t.Fatalf("Failed to recreate chain: %v", err)
}
defer chain.Stop()
}
// Iterate over all the remaining blocks and ensure there are no gaps
verifyNoGaps(t, chain, true, blocks)
verifyCutoff(t, chain, true, blocks, tt.expCanonicalBlocks)
if head := chain.CurrentHeader(); head.Number.Uint64() != tt.expHeadHeader {
t.Errorf("Head header mismatch: have %d, want %d", head.Number, tt.expHeadHeader)
}
if head := chain.CurrentFastBlock(); head.NumberU64() != tt.expHeadFastBlock {
t.Errorf("Head fast block mismatch: have %d, want %d", head.NumberU64(), tt.expHeadFastBlock)
}
if head := chain.CurrentBlock(); head.NumberU64() != tt.expHeadBlock {
t.Errorf("Head block mismatch: have %d, want %d", head.NumberU64(), tt.expHeadBlock)
}
// Check the disk layer, ensure they are matched
block := chain.GetBlockByNumber(tt.expSnapshotBottom)
if block == nil {
t.Errorf("The correspnding block[%d] of snapshot disk layer is missing", tt.expSnapshotBottom)
} else if !bytes.Equal(chain.snaps.DiskRoot().Bytes(), block.Root().Bytes()) {
t.Errorf("The snapshot disk layer root is incorrect, want %x, get %x", block.Root(), chain.snaps.DiskRoot())
}
}