github.com/pingcap/ticdc@v0.0.0-20220526033649-485a10ef2652/pkg/scheduler/workload.go (about)

     1  // Copyright 2020 PingCAP, Inc.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // See the License for the specific language governing permissions and
    12  // limitations under the License.
    13  
    14  package scheduler
    15  
    16  import (
    17  	"math"
    18  
    19  	"github.com/pingcap/ticdc/cdc/model"
    20  )
    21  
    22  type workloads map[model.CaptureID]model.TaskWorkload
    23  
    24  func (w workloads) SetCapture(captureID model.CaptureID, workloads model.TaskWorkload) {
    25  	w[captureID] = workloads
    26  }
    27  
    28  func (w workloads) AlignCapture(captureIDs map[model.CaptureID]struct{}) {
    29  	for captureID := range captureIDs {
    30  		if _, exist := w[captureID]; !exist {
    31  			w[captureID] = make(model.TaskWorkload)
    32  		}
    33  	}
    34  	for captureID := range w {
    35  		if _, exist := captureIDs[captureID]; !exist {
    36  			delete(w, captureID)
    37  		}
    38  	}
    39  }
    40  
    41  func (w workloads) SetTable(captureID model.CaptureID, tableID model.TableID, workload model.WorkloadInfo) {
    42  	captureWorkloads, exist := w[captureID]
    43  	if !exist {
    44  		captureWorkloads = make(model.TaskWorkload)
    45  		w[captureID] = captureWorkloads
    46  	}
    47  	captureWorkloads[tableID] = workload
    48  }
    49  
    50  func (w workloads) RemoveTable(captureID model.CaptureID, tableID model.TableID) {
    51  	captureWorkloads, exist := w[captureID]
    52  	if !exist {
    53  		return
    54  	}
    55  	delete(captureWorkloads, tableID)
    56  }
    57  
    58  func (w workloads) AvgEachTable() uint64 {
    59  	var totalWorkload uint64
    60  	var totalTable uint64
    61  	for _, captureWorkloads := range w {
    62  		for _, workload := range captureWorkloads {
    63  			totalWorkload += workload.Workload
    64  		}
    65  		totalTable += uint64(len(captureWorkloads))
    66  	}
    67  	return totalWorkload / totalTable
    68  }
    69  
    70  func (w workloads) Skewness() float64 {
    71  	totalWorkloads := make([]uint64, 0, len(w))
    72  	var workloadSum uint64
    73  	for _, captureWorkloads := range w {
    74  		var total uint64
    75  		for _, workload := range captureWorkloads {
    76  			total += workload.Workload
    77  		}
    78  		totalWorkloads = append(totalWorkloads, total)
    79  		workloadSum += total
    80  	}
    81  	avgWorkload := float64(workloadSum) / float64(len(w))
    82  
    83  	var totalVariance float64
    84  	for _, totalWorkload := range totalWorkloads {
    85  		totalVariance += math.Pow((float64(totalWorkload)/avgWorkload)-1, 2)
    86  	}
    87  	return math.Sqrt(totalVariance / float64(len(w)))
    88  }
    89  
    90  func (w workloads) SelectIdleCapture() model.CaptureID {
    91  	minWorkload := uint64(math.MaxUint64)
    92  	var minCapture model.CaptureID
    93  	for captureID, captureWorkloads := range w {
    94  		var totalWorkloadInCapture uint64
    95  		for _, workload := range captureWorkloads {
    96  			totalWorkloadInCapture += workload.Workload
    97  		}
    98  		if minWorkload > totalWorkloadInCapture {
    99  			minWorkload = totalWorkloadInCapture
   100  			minCapture = captureID
   101  		}
   102  	}
   103  	return minCapture
   104  }
   105  
   106  func (w workloads) Clone() workloads {
   107  	cloneWorkloads := make(map[model.CaptureID]model.TaskWorkload, len(w))
   108  	for captureID, captureWorkloads := range w {
   109  		cloneCaptureWorkloads := make(model.TaskWorkload, len(captureWorkloads))
   110  		for tableID, workload := range captureWorkloads {
   111  			cloneCaptureWorkloads[tableID] = workload
   112  		}
   113  		cloneWorkloads[captureID] = cloneCaptureWorkloads
   114  	}
   115  	return cloneWorkloads
   116  }