81 lines
1.9 KiB
Go
81 lines
1.9 KiB
Go
// Copyright 2020 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 kv
|
|
|
|
import (
|
|
"context"
|
|
"sync"
|
|
)
|
|
|
|
type (
|
|
cachedb struct {
|
|
mu sync.RWMutex
|
|
memTables map[int64]*memdb
|
|
}
|
|
|
|
// MemManager add in executor and tikv for reduce query tikv
|
|
MemManager interface {
|
|
Set(tableID int64, key Key, value []byte) error
|
|
Get(ctx context.Context, tableID int64, key Key) []byte
|
|
Delete(tableID int64)
|
|
}
|
|
)
|
|
|
|
// Set set value in cache
|
|
func (c *cachedb) Set(tableID int64, key Key, value []byte) error {
|
|
c.mu.Lock()
|
|
defer c.mu.Unlock()
|
|
table, ok := c.memTables[tableID]
|
|
if !ok {
|
|
table = newMemDB()
|
|
c.memTables[tableID] = table
|
|
}
|
|
err := table.Set(key, value)
|
|
if err != nil && ErrTxnTooLarge.Equal(err) {
|
|
// If it reaches the upper limit, refresh a new memory buffer.
|
|
c.memTables[tableID] = newMemDB()
|
|
return nil
|
|
}
|
|
return err
|
|
}
|
|
|
|
// Get gets value from memory
|
|
func (c *cachedb) Get(ctx context.Context, tableID int64, key Key) []byte {
|
|
c.mu.RLock()
|
|
defer c.mu.RUnlock()
|
|
if table, ok := c.memTables[tableID]; ok {
|
|
if val, err := table.Get(ctx, key); err == nil {
|
|
return val
|
|
}
|
|
}
|
|
return nil
|
|
}
|
|
|
|
// Delete delete and reset table from tables in memory by tableID
|
|
func (c *cachedb) Delete(tableID int64) {
|
|
c.mu.Lock()
|
|
if k, ok := c.memTables[tableID]; ok {
|
|
k.Reset()
|
|
delete(c.memTables, tableID)
|
|
}
|
|
c.mu.Unlock()
|
|
}
|
|
|
|
// NewCacheDB new cachedb
|
|
func NewCacheDB() MemManager {
|
|
mm := new(cachedb)
|
|
mm.memTables = make(map[int64]*memdb)
|
|
return mm
|
|
}
|