Files
tidb/pkg/disttask/framework/proto/step.go

139 lines
4.2 KiB
Go

// Copyright 2024 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 proto
import "fmt"
// Step is the step of task.
type Step int64
// TaskStep is the step of task.
// DO NOT change the value of the constants, will break backward compatibility.
// successfully task MUST go from StepInit to business steps, then StepDone.
const (
StepInit Step = -1
StepDone Step = -2
)
// Step2Str converts step to string.
// it's too bad that we define step as int 🙃.
func Step2Str(t TaskType, s Step) string {
// StepInit and StepDone are special steps, we don't check task type for them.
if s == StepInit {
return "init"
} else if s == StepDone {
return "done"
}
switch t {
case Backfill:
return backfillStep2Str(s)
case ImportInto:
return importIntoStep2Str(s)
case TaskTypeExample:
return exampleStep2Str(s)
}
return fmt.Sprintf("unknown type %s", t)
}
// Steps of example task type, they can either have 1 or 2 steps.
const (
StepOne Step = 1
StepTwo Step = 2
)
func exampleStep2Str(s Step) string {
switch s {
case StepOne:
return "one"
case StepTwo:
return "two"
default:
return fmt.Sprintf("unknown step %d", s)
}
}
// Steps of IMPORT INTO, each step is represented by one or multiple subtasks.
// the initial step is StepInit(-1)
// steps are processed in the following order:
// - local sort: StepInit -> ImportStepImport -> ImportStepPostProcess -> StepDone
// - global sort:
// StepInit -> ImportStepEncodeAndSort -> ImportStepMergeSort -> ImportStepWriteAndIngest
// -> ImportStepPostProcess -> StepDone
const (
// ImportStepImport we sort source data and ingest it into TiKV in this step.
ImportStepImport Step = 1
// ImportStepPostProcess we verify checksum and add index in this step.
ImportStepPostProcess Step = 2
// ImportStepEncodeAndSort encode source data and write sorted kv into global storage.
ImportStepEncodeAndSort Step = 3
// ImportStepMergeSort merge sorted kv from global storage, so we can have better
// read performance during ImportStepWriteAndIngest.
// depends on how much kv files are overlapped, there's might 0 subtasks
// in this step.
ImportStepMergeSort Step = 4
// ImportStepWriteAndIngest write sorted kv into TiKV and ingest it.
ImportStepWriteAndIngest Step = 5
)
func importIntoStep2Str(s Step) string {
switch s {
case ImportStepImport:
return "import"
case ImportStepPostProcess:
return "post-process"
case ImportStepEncodeAndSort:
return "encode&sort"
case ImportStepMergeSort:
return "merge-sort"
case ImportStepWriteAndIngest:
return "write&ingest"
default:
return fmt.Sprintf("unknown step %d", s)
}
}
// Steps of Add Index, each step is represented by one or multiple subtasks.
// the initial step is StepInit(-1)
// steps are processed in the following order:
// - local sort:
// StepInit -> BackfillStepReadIndex -> StepDone
// - global sort:
// StepInit -> BackfillStepReadIndex -> BackfillStepMergeSort -> BackfillStepWriteAndIngest -> StepDone
const (
BackfillStepReadIndex Step = 1
// BackfillStepMergeSort only used in global sort, it will merge sorted kv from global storage, so we can have better
// read performance during BackfillStepWriteAndIngest with global sort.
// depends on how much kv files are overlapped.
// When kv files overlapped less than MergeSortOverlapThreshold, there‘re no subtasks.
BackfillStepMergeSort Step = 2
// BackfillStepWriteAndIngest write sorted kv into TiKV and ingest it.
BackfillStepWriteAndIngest Step = 3
)
// StepStr convert proto.Step to string.
func backfillStep2Str(s Step) string {
switch s {
case BackfillStepReadIndex:
return "read-index"
case BackfillStepMergeSort:
return "merge-sort"
case BackfillStepWriteAndIngest:
return "write&ingest"
default:
return fmt.Sprintf("unknown step %d", s)
}
}