tidb mpp 代码
文件路径：/kv/mpp.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,
/ 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 kv
import (
"context"
"time"
"github.com/pingcap/kvproto/pkg/mpp"
)
/ MPPTaskMeta means the meta info such as location of a mpp task.
type MPPTaskMeta interface {
/ GetAddress indicates which node this task should execute on.
GetAddress() string
}
/ MPPTask means the minimum execution unit of a mpp computation job.
type MPPTask struct {
Meta MPPTaskMeta / on which store this task will execute
ID int64 / mppTaskID
StartTs uint64
TableID int64 / physical table id
PartitionTableIDs []int64
}
/ ToPB generates the pb structure.
func (t *MPPTask) ToPB() *mpp.TaskMeta {
meta := &mpp.TaskMeta{
StartTs: t.StartTs,
TaskId: t.ID,
}
if t.ID != -1 {
meta.Address = t.Meta.GetAddress()
}
return meta
}
/ MppTaskStates denotes the state of mpp tasks
type MppTaskStates uint8
const (
/ MppTaskReady means the task is ready
MppTaskReady MppTaskStates = iota
/ MppTaskRunning means the task is running
MppTaskRunning
/ MppTaskCancelled means the task is cancelled
MppTaskCancelled
/ MppTaskDone means the task is done
MppTaskDone
)
/ MPPDispatchRequest stands for a dispatching task.
type MPPDispatchRequest struct {
Data []byte / data encodes the dag coprocessor request.
Meta MPPTaskMeta / mpp store is the location of tiflash store.
IsRoot bool / root task returns data to tidb directly.
Timeout uint64 / If task is assigned but doesn't receive a connect request during timeout, the task should be destroyed.
/ SchemaVer is for any schema-ful storage (like tiflash) to validate schema correctness if necessary.
SchemaVar int64
StartTs uint64
ID int64 / identify a single task
State MppTaskStates
}
/ MPPClient accepts and processes mpp requests.
type MPPClient interface {
/ ConstructMPPTasks schedules task for a plan fragment.
/ TODO:: This interface will be refined after we support more executors.
ConstructMPPTasks(context.Context, *MPPBuildTasksRequest, map[string]time.Time, time.Duration) ([]MPPTaskMeta, error)
/ DispatchMPPTasks dispatches ALL mpp requests at once, and returns an iterator that transfers the data.
DispatchMPPTasks(ctx context.Context, vars interface{}, reqs []*MPPDispatchRequest, needTriggerFallback bool, startTs uint64) Response
}
/ MPPBuildTasksRequest request the stores allocation for a mpp plan fragment.
/ However, the request doesn't contain the particular plan, because only key ranges take effect on the location assignment.
type MPPBuildTasksRequest struct {
KeyRanges []KeyRange
StartTS uint64
PartitionIDAndRanges []PartitionIDAndRanges
}