tidb sli 代码
文件路径：/util/sli/sli.go
/ Copyright 2021 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 sli
import (
"fmt"
"time"
"github.com/pingcap/failpoint"
"github.com/pingcap/tidb/metrics"
)
/ TxnWriteThroughputSLI uses to report transaction write throughput metrics for SLI.
type TxnWriteThroughputSLI struct {
invalid bool
affectRow uint64
writeSize int
readKeys int
writeKeys int
writeTime time.Duration
}
/ FinishExecuteStmt records the cost for write statement which affect rows more than 0.
/ And report metrics when the transaction is committed.
func (t *TxnWriteThroughputSLI) FinishExecuteStmt(cost time.Duration, affectRow uint64, inTxn bool) {
if affectRow > 0 {
t.writeTime += cost
t.affectRow += affectRow
}
/ Currently not in transaction means the last transaction is finish, should report metrics and reset data.
if !inTxn {
if affectRow == 0 {
/ AffectRows is 0 when statement is commit.
t.writeTime += cost
}
/ Report metrics after commit this transaction.
t.reportMetric()
/ Skip reset for test.
failpoint.Inject("CheckTxnWriteThroughput", func() {
failpoint.Return()
})
/ Reset for next transaction.
t.Reset()
}
}
/ AddReadKeys adds the read keys.
func (t *TxnWriteThroughputSLI) AddReadKeys(readKeys int64) {
t.readKeys += int(readKeys)
}
/ AddTxnWriteSize adds the transaction write size and keys.
func (t *TxnWriteThroughputSLI) AddTxnWriteSize(size, keys int) {
t.writeSize += size
t.writeKeys += keys
}
func (t *TxnWriteThroughputSLI) reportMetric() {
if t.IsInvalid() {
return
}
if t.IsSmallTxn() {
metrics.SmallTxnWriteDuration.Observe(t.writeTime.Seconds())
} else {
metrics.TxnWriteThroughput.Observe(float64(t.writeSize) / t.writeTime.Seconds())
}
}
/ SetInvalid marks this transaction is invalid to report SLI metrics.
func (t *TxnWriteThroughputSLI) SetInvalid() {
t.invalid = true
}
/ IsInvalid checks the transaction is valid to report SLI metrics. Currently, the following case will cause invalid:
/ 1. The transaction contains `insert|replace into ... select ... from ...` statement.
/ 2. The write SQL statement has more read keys than write keys.
func (t *TxnWriteThroughputSLI) IsInvalid() bool {
return t.invalid || t.readKeys > t.writeKeys || t.writeSize == 0 || t.writeTime == 0
}
const (
smallTxnAffectRow = 20
smallTxnSize = 1 * 1024 * 1024 / 1MB
)
/ IsSmallTxn exports for testing.
func (t *TxnWriteThroughputSLI) IsSmallTxn() bool {
return t.affectRow <= smallTxnAffectRow && t.writeSize <= smallTxnSize
}
/ Reset exports for testing.
func (t *TxnWriteThroughputSLI) Reset() {
t.invalid = false
t.affectRow = 0
t.writeSize = 0
t.readKeys = 0
t.writeKeys = 0
t.writeTime = 0
}
/ String exports for testing.
func (t *TxnWriteThroughputSLI) String() string {
return fmt.Sprintf("invalid: %v, affectRow: %v, writeSize: %v, readKeys: %v, writeKeys: %v, writeTime: %v",
t.invalid, t.affectRow, t.writeSize, t.readKeys, t.writeKeys, t.writeTime.String())
}