Files
tidb/pkg/executor/internal/pdhelper/pd_test.go

70 lines
2.6 KiB
Go

// Copyright 2023 PingCAP, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package pdhelper
import (
"context"
"testing"
"time"
"github.com/jellydator/ttlcache/v3"
"github.com/pingcap/tidb/pkg/sessionctx"
"github.com/stretchr/testify/require"
)
var globalMockClient mockClient
type mockClient struct {
missCnt int
}
func (m *mockClient) getMissCnt() int {
return m.missCnt
}
func (m *mockClient) getFakeApproximateTableCountFromStorage(_ context.Context, _ sessionctx.Context, _ int64, _, _, _ string) (float64, bool) {
m.missCnt++
return 1.0, true
}
func TestTTLCache(t *testing.T) {
cache := ttlcache.New[string, float64](
ttlcache.WithTTL[string, float64](100*time.Millisecond),
ttlcache.WithCapacity[string, float64](2),
)
helper := &PDHelper{
cacheForApproximateTableCountFromStorage: cache,
getApproximateTableCountFromStorageFunc: globalMockClient.getFakeApproximateTableCountFromStorage,
}
ctx := context.Background()
helper.GetApproximateTableCountFromStorage(ctx, nil, 1, "db", "table", "partition") // Miss
require.Equal(t, 1, globalMockClient.getMissCnt())
helper.GetApproximateTableCountFromStorage(ctx, nil, 1, "db", "table", "partition") // Hit
require.Equal(t, 1, globalMockClient.getMissCnt())
helper.GetApproximateTableCountFromStorage(ctx, nil, 2, "db1", "table1", "partition") // Miss
require.Equal(t, 2, globalMockClient.getMissCnt())
helper.GetApproximateTableCountFromStorage(ctx, nil, 3, "db2", "table2", "partition") // Miss
helper.GetApproximateTableCountFromStorage(ctx, nil, 1, "db", "table", "partition") // Miss
require.Equal(t, 4, globalMockClient.getMissCnt())
helper.GetApproximateTableCountFromStorage(ctx, nil, 3, "db2", "table2", "partition") // Hit
require.Equal(t, 4, globalMockClient.getMissCnt())
time.Sleep(200 * time.Millisecond)
// All is miss.
helper.GetApproximateTableCountFromStorage(ctx, nil, 1, "db", "table", "partition")
helper.GetApproximateTableCountFromStorage(ctx, nil, 2, "db1", "table1", "partition")
helper.GetApproximateTableCountFromStorage(ctx, nil, 3, "db2", "table2", "partition")
require.Equal(t, 7, globalMockClient.getMissCnt())
}