Files
tidb/bindinfo/cache.go
2019-08-26 10:30:40 +08:00

86 lines
2.5 KiB
Go

// Copyright 2019 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,
// See the License for the specific language governing permissions and
// limitations under the License.
package bindinfo
import (
"unsafe"
"github.com/pingcap/tidb/metrics"
"github.com/pingcap/tidb/types"
"github.com/pingcap/tidb/util/chunk"
)
const (
// Using is the bind info's in use status.
Using = "using"
// deleted is the bind info's deleted status.
deleted = "deleted"
// Invalid is the bind info's invalid status.
Invalid = "invalid"
)
// BindMeta stores the basic bind info and bindSql astNode.
type BindMeta struct {
*BindRecord
// HintSet stores the set of hints of binding sql.
*HintsSet
}
// cache is a k-v map, key is original sql, value is a slice of BindMeta.
type cache map[string][]*BindMeta
// BindRecord represents a sql bind record retrieved from the storage.
type BindRecord struct {
OriginalSQL string
BindSQL string
Db string
// Status represents the status of the binding. It can only be one of the following values:
// 1. deleted: BindRecord is deleted, can not be used anymore.
// 2. using: BindRecord is in the normal active mode.
Status string
CreateTime types.Time
UpdateTime types.Time
Charset string
Collation string
}
func newBindRecord(row chunk.Row) *BindRecord {
return &BindRecord{
OriginalSQL: row.GetString(0),
BindSQL: row.GetString(1),
Db: row.GetString(2),
Status: row.GetString(3),
CreateTime: row.GetTime(4),
UpdateTime: row.GetTime(5),
Charset: row.GetString(6),
Collation: row.GetString(7),
}
}
// size calculates the memory size of a bind meta.
func (m *BindRecord) size() float64 {
res := len(m.OriginalSQL) + len(m.BindSQL) + len(m.Db) + len(m.Status) + 2*int(unsafe.Sizeof(m.CreateTime)) + len(m.Charset) + len(m.Collation)
return float64(res)
}
func (m *BindRecord) updateMetrics(scope string, inc bool) {
if inc {
metrics.BindMemoryUsage.WithLabelValues(scope, m.Status).Add(float64(m.size()))
metrics.BindTotalGauge.WithLabelValues(scope, m.Status).Inc()
} else {
metrics.BindMemoryUsage.WithLabelValues(scope, m.Status).Sub(float64(m.size()))
metrics.BindTotalGauge.WithLabelValues(scope, m.Status).Dec()
}
}