From 26534429becdd1f3e65ec1f9f781078585449173 Mon Sep 17 00:00:00 2001 From: crazycs Date: Mon, 27 May 2024 12:05:49 +0800 Subject: [PATCH] This is an automated cherry-pick of #53445 Signed-off-by: ti-chi-bot --- domain/domain.go | 2 + executor/kvtest/BUILD.bazel | 4 + infoschema/cache.go | 83 +++++++++++++++++ infoschema/cache_test.go | 172 ++++++++++++++++++++++++++++++++++++ 4 files changed, 261 insertions(+) diff --git a/domain/domain.go b/domain/domain.go index 00e3a42e9be9f..6f9a262db636c 100644 --- a/domain/domain.go +++ b/domain/domain.go @@ -417,6 +417,8 @@ func (do *Domain) tryLoadSchemaDiffs(m *meta.Meta, usedVersion, newVersion int64 if diff == nil { // Empty diff means the txn of generating schema version is committed, but the txn of `runDDLJob` is not or fail. // It is safe to skip the empty diff because the infoschema is new enough and consistent. + logutil.BgLogger().Info("diff load InfoSchema get empty schema diff", zap.Int64("version", usedVersion)) + do.infoCache.InsertEmptySchemaVersion(usedVersion) continue } diffs = append(diffs, diff) diff --git a/executor/kvtest/BUILD.bazel b/executor/kvtest/BUILD.bazel index c746c6013029f..7b6f3b0d6bacc 100644 --- a/executor/kvtest/BUILD.bazel +++ b/executor/kvtest/BUILD.bazel @@ -8,7 +8,11 @@ go_test( "main_test.go", ], flaky = True, +<<<<<<< HEAD:executor/kvtest/BUILD.bazel race = "on", +======= + shard_count = 8, +>>>>>>> 0ac2ad0252b (infoschema: fix issue of information schema cache miss cause by schema version gap (#53445)):pkg/infoschema/test/cachetest/BUILD.bazel deps = [ "//config", "//meta/autoid", diff --git a/infoschema/cache.go b/infoschema/cache.go index da351c81bf2d2..e8ed98fbb88f5 100644 --- a/infoschema/cache.go +++ b/infoschema/cache.go @@ -30,6 +30,15 @@ type InfoCache struct { mu sync.RWMutex // cache is sorted by both SchemaVersion and timestamp in descending order, assume they have same order cache []schemaAndTimestamp +<<<<<<< HEAD:infoschema/cache.go +======= + + // emptySchemaVersions stores schema version which has no schema_diff. + emptySchemaVersions map[int64]struct{} + + r autoid.Requirement + Data *Data +>>>>>>> 0ac2ad0252b (infoschema: fix issue of information schema cache miss cause by schema version gap (#53445)):pkg/infoschema/cache.go } type schemaAndTimestamp struct { @@ -40,7 +49,14 @@ type schemaAndTimestamp struct { // NewCache creates a new InfoCache. func NewCache(capacity int) *InfoCache { return &InfoCache{ +<<<<<<< HEAD:infoschema/cache.go cache: make([]schemaAndTimestamp, 0, capacity), +======= + cache: make([]schemaAndTimestamp, 0, capacity), + emptySchemaVersions: make(map[int64]struct{}), + r: r, + Data: infoData, +>>>>>>> 0ac2ad0252b (infoschema: fix issue of information schema cache miss cause by schema version gap (#53445)):pkg/infoschema/cache.go } } @@ -63,6 +79,19 @@ func (h *InfoCache) GetLatest() InfoSchema { return nil } +<<<<<<< HEAD:infoschema/cache.go +======= +// Len returns the size of the cache +func (h *InfoCache) Len() int { + return len(h.cache) +} + +// GetEmptySchemaVersions returns emptySchemaVersions, exports for testing. +func (h *InfoCache) GetEmptySchemaVersions() map[int64]struct{} { + return h.emptySchemaVersions +} + +>>>>>>> 0ac2ad0252b (infoschema: fix issue of information schema cache miss cause by schema version gap (#53445)):pkg/infoschema/cache.go func (h *InfoCache) getSchemaByTimestampNoLock(ts uint64) (InfoSchema, bool) { logutil.BgLogger().Debug("SCHEMA CACHE get schema", zap.Uint64("timestamp", ts)) // search one by one instead of binary search, because the timestamp of a schema could be 0 @@ -79,6 +108,38 @@ func (h *InfoCache) getSchemaByTimestampNoLock(ts uint64) (InfoSchema, bool) { // found the largest version before the given ts return is.infoschema, true } +<<<<<<< HEAD:infoschema/cache.go +======= + + if uint64(h.cache[i-1].timestamp) > ts { + // The first condition is to make sure the cache[i-1].timestamp > ts >= cache[i].timestamp, then the current schema is suitable for ts. + lastVersion := h.cache[i-1].infoschema.SchemaMetaVersion() + currentVersion := is.infoschema.SchemaMetaVersion() + if lastVersion == currentVersion+1 { + // This condition is to make sure the schema version is continuous. If last(cache[i-1]) schema-version is 10, + // but current(cache[i]) schema-version is not 9, then current schema may not suitable for ts. + return is.infoschema, true + } + if lastVersion > currentVersion { + found := true + for ver := currentVersion + 1; ver < lastVersion; ver++ { + _, ok := h.emptySchemaVersions[ver] + if !ok { + found = false + break + } + } + if found { + // This condition is to make sure the schema version is continuous. If last(cache[i-1]) schema-version is 10, and + // current(cache[i]) schema-version is 8, then there is a gap exist, and if all the gap version can be found in cache.emptySchemaVersions + // which means those gap versions don't have schema info, then current schema is also suitable for ts. + return is.infoschema, true + } + } + } + // current schema is not suitable for ts, then break the loop to avoid the unnecessary search. + break +>>>>>>> 0ac2ad0252b (infoschema: fix issue of information schema cache miss cause by schema version gap (#53445)):pkg/infoschema/cache.go } logutil.BgLogger().Debug("SCHEMA CACHE no schema found") @@ -185,3 +246,25 @@ func (h *InfoCache) Insert(is InfoSchema, schemaTS uint64) bool { return true } + +// InsertEmptySchemaVersion inserts empty schema version into a map. If exceeded the cache capacity, remove the oldest version. +func (h *InfoCache) InsertEmptySchemaVersion(version int64) { + h.mu.Lock() + defer h.mu.Unlock() + + h.emptySchemaVersions[version] = struct{}{} + if len(h.emptySchemaVersions) > cap(h.cache) { + // remove oldest version. + versions := make([]int64, 0, len(h.emptySchemaVersions)) + for ver := range h.emptySchemaVersions { + versions = append(versions, ver) + } + sort.Slice(versions, func(i, j int) bool { return versions[i] < versions[j] }) + for _, ver := range versions { + delete(h.emptySchemaVersions, ver) + if len(h.emptySchemaVersions) <= cap(h.cache) { + break + } + } + } +} diff --git a/infoschema/cache_test.go b/infoschema/cache_test.go index b05ffa531fae5..6c65090bd7a45 100644 --- a/infoschema/cache_test.go +++ b/infoschema/cache_test.go @@ -164,4 +164,176 @@ func TestGetByTimestamp(t *testing.T) { require.Nil(t, ic.GetBySnapshotTS(2)) require.Equal(t, is3, ic.GetBySnapshotTS(3)) require.Equal(t, is3, ic.GetBySnapshotTS(4)) +<<<<<<< HEAD:infoschema/cache_test.go +======= + require.Equal(t, 3, ic.Len()) + + // insert is2 again with correct timestamp, to correct previous wrong timestamp + ic.Insert(is2, 2) + require.Equal(t, is3, ic.GetLatest()) + require.Equal(t, is1, ic.GetBySnapshotTS(1)) + require.Equal(t, is2, ic.GetBySnapshotTS(2)) + require.Equal(t, is3, ic.GetBySnapshotTS(3)) + require.Equal(t, 3, ic.Len()) +} + +func TestReSize(t *testing.T) { + ic := infoschema.NewCache(nil, 2) + require.NotNil(t, ic) + is1 := infoschema.MockInfoSchemaWithSchemaVer(nil, 1) + ic.Insert(is1, 1) + is2 := infoschema.MockInfoSchemaWithSchemaVer(nil, 2) + ic.Insert(is2, 2) + + ic.ReSize(3) + require.Equal(t, 2, ic.Size()) + require.Equal(t, is1, ic.GetByVersion(1)) + require.Equal(t, is2, ic.GetByVersion(2)) + is3 := infoschema.MockInfoSchemaWithSchemaVer(nil, 3) + require.True(t, ic.Insert(is3, 3)) + require.Equal(t, is1, ic.GetByVersion(1)) + require.Equal(t, is2, ic.GetByVersion(2)) + require.Equal(t, is3, ic.GetByVersion(3)) + + ic.ReSize(1) + require.Equal(t, 1, ic.Size()) + require.Nil(t, ic.GetByVersion(1)) + require.Nil(t, ic.GetByVersion(2)) + require.Equal(t, is3, ic.GetByVersion(3)) + require.False(t, ic.Insert(is2, 2)) + require.Equal(t, 1, ic.Size()) + is4 := infoschema.MockInfoSchemaWithSchemaVer(nil, 4) + require.True(t, ic.Insert(is4, 4)) + require.Equal(t, 1, ic.Size()) + require.Nil(t, ic.GetByVersion(1)) + require.Nil(t, ic.GetByVersion(2)) + require.Nil(t, ic.GetByVersion(3)) + require.Equal(t, is4, ic.GetByVersion(4)) +} + +func TestCacheWithSchemaTsZero(t *testing.T) { + ic := infoschema.NewCache(nil, 16) + require.NotNil(t, ic) + + for i := 1; i <= 8; i++ { + ic.Insert(infoschema.MockInfoSchemaWithSchemaVer(nil, int64(i)), uint64(i)) + } + + checkFn := func(start, end int64, exist bool) { + require.True(t, start <= end) + latestSchemaVersion := ic.GetLatest().SchemaMetaVersion() + for ts := start; ts <= end; ts++ { + is := ic.GetBySnapshotTS(uint64(ts)) + if exist { + require.NotNil(t, is, fmt.Sprintf("ts %d", ts)) + if ts > latestSchemaVersion { + require.Equal(t, latestSchemaVersion, is.SchemaMetaVersion(), fmt.Sprintf("ts %d", ts)) + } else { + require.Equal(t, ts, is.SchemaMetaVersion(), fmt.Sprintf("ts %d", ts)) + } + } else { + require.Nil(t, is, fmt.Sprintf("ts %d", ts)) + } + } + } + checkFn(1, 8, true) + checkFn(8, 10, true) + + // mock for meet error There is no Write MVCC info for the schema version + ic.Insert(infoschema.MockInfoSchemaWithSchemaVer(nil, 9), 0) + checkFn(1, 7, true) + checkFn(8, 9, false) + checkFn(9, 10, false) + + for i := 10; i <= 16; i++ { + ic.Insert(infoschema.MockInfoSchemaWithSchemaVer(nil, int64(i)), uint64(i)) + checkFn(1, 7, true) + checkFn(8, 9, false) + checkFn(10, 16, true) + } + require.Equal(t, 16, ic.Size()) + + // refill the cache + ic.Insert(infoschema.MockInfoSchemaWithSchemaVer(nil, 9), 9) + checkFn(1, 16, true) + require.Equal(t, 16, ic.Size()) + + // Test more than capacity + ic.Insert(infoschema.MockInfoSchemaWithSchemaVer(nil, 17), 17) + checkFn(1, 1, false) + checkFn(2, 17, true) + checkFn(2, 20, true) + require.Equal(t, 16, ic.Size()) + + // Test for there is a hole in the middle. + ic = infoschema.NewCache(nil, 16) + + // mock for restart with full load the latest version schema. + ic.Insert(infoschema.MockInfoSchemaWithSchemaVer(nil, 100), 100) + checkFn(1, 99, false) + checkFn(100, 100, true) + + for i := 1; i <= 16; i++ { + ic.Insert(infoschema.MockInfoSchemaWithSchemaVer(nil, int64(i)), uint64(i)) + } + checkFn(1, 1, false) + checkFn(2, 15, true) + checkFn(16, 16, false) + checkFn(100, 100, true) + require.Equal(t, 16, ic.Size()) + + for i := 85; i < 100; i++ { + ic.Insert(infoschema.MockInfoSchemaWithSchemaVer(nil, int64(i)), uint64(i)) + } + checkFn(1, 84, false) + checkFn(85, 100, true) + require.Equal(t, 16, ic.Size()) + + // Test cache with schema version hole, which is cause by schema version doesn't has related schema-diff. + ic = infoschema.NewCache(nil, 16) + require.NotNil(t, ic) + for i := 1; i <= 8; i++ { + ic.Insert(infoschema.MockInfoSchemaWithSchemaVer(nil, int64(i)), uint64(i)) + } + checkFn(1, 10, true) + // mock for schema version hole, schema-version 9 is missing. + ic.Insert(infoschema.MockInfoSchemaWithSchemaVer(nil, 10), 10) + checkFn(1, 7, true) + // without empty schema version map, get snapshot by ts 8, 9 will both failed. + checkFn(8, 9, false) + checkFn(10, 10, true) + // add empty schema version 9. + ic.InsertEmptySchemaVersion(9) + // after set empty schema version, get snapshot by ts 8, 9 will both success. + checkFn(1, 8, true) + checkFn(10, 10, true) + is := ic.GetBySnapshotTS(uint64(9)) + require.NotNil(t, is) + // since schema version 9 is empty, so get by ts 9 will get schema which version is 8. + require.Equal(t, int64(8), is.SchemaMetaVersion()) +} + +func TestCacheEmptySchemaVersion(t *testing.T) { + ic := infoschema.NewCache(nil, 16) + require.NotNil(t, ic) + require.Equal(t, 0, len(ic.GetEmptySchemaVersions())) + for i := 0; i < 16; i++ { + ic.InsertEmptySchemaVersion(int64(i)) + } + emptyVersions := ic.GetEmptySchemaVersions() + require.Equal(t, 16, len(emptyVersions)) + for i := 0; i < 16; i++ { + _, ok := emptyVersions[int64(i)] + require.True(t, ok) + } + for i := 16; i < 20; i++ { + ic.InsertEmptySchemaVersion(int64(i)) + } + emptyVersions = ic.GetEmptySchemaVersions() + require.Equal(t, 16, len(emptyVersions)) + for i := 4; i < 20; i++ { + _, ok := emptyVersions[int64(i)] + require.True(t, ok) + } +>>>>>>> 0ac2ad0252b (infoschema: fix issue of information schema cache miss cause by schema version gap (#53445)):pkg/infoschema/test/cachetest/cache_test.go }