Merged in genericTaskSorter (pull request #18)

GenericTaskSorter

Approved-by: Renan DelValle <rdelval1@binghamton.edu>
Approved-by: ajain13 <ajain13@binghamton.edu>

README.md

@@ -16,11 +16,11 @@ To Do:
  * Have a centralised logFile that can be filtered by identifier. All electron logs should go into this file.
  * Make def.Task an interface for further modularization and flexibility.
  * Convert def#WattsToConsider(...) to be a receiver of def.Task and change the name of it to Watts(...).
- * Have a generic sorter for task resources instead of having one for each kind of resource.
  *  **Critical** -- Add software requirements to the README.md (Mesos version, RAPL version, PCP version, Go version...)
  *  **Critical** -- Retrofit to use Go 1.8 sorting techniques. Use def/taskUtils.go for reference.
  * Handle powerclass not configured on a node condition. As of now, an assumption is made that the powerclass is configured
  * Refine the sorting algorithm that sorts the clusters of tasks retrieved using the kmeans algorithm. This also involves the reduction in time complexity of the same.
+ * Use the generic task sorter in def/taskUtils.go to sort the tasks based on CPU or RAM etc. Remove the existing sorters present in def/task.go.
    for all the nodes.
 
 **Requires [Performance Co-Pilot](http://pcp.io/) tool pmdumptext to be installed on the

def/sortingCriteria.go

@@ -0,0 +1,13 @@
+package def
+
+// the sortBy function that takes a task reference and returns the resource to consider when sorting.
+type sortBy func(task *Task) float64
+
+// Possible Sorting Criteria
+// Each holds a closure that fetches the required resource from the
+// 	given task reference.
+var (
+	SortByCPU   = func(task *Task) float64 { return task.CPU }
+	SortByRAM   = func(task *Task) float64 { return task.RAM }
+	SortByWatts = func(task *Task) float64 { return task.Watts }
+)

def/taskUtils.go

@@ -2,8 +2,8 @@ package def
 
 import (
 	"github.com/mdesenfants/gokmeans"
-	"sort"
 	"log"
+	"sort"
 )
 
 // Information about a cluster of tasks
@@ -114,3 +114,11 @@ func labelAndOrder(clusters map[int][]Task, numberOfClusters int, taskObservatio
 	})
 	return sizedClusters
 }
+
+// Generic Task Sorter.
+// Be able to sort an array of tasks based on any of the tasks' resources.
+func SortTasks(ts []Task, sb sortBy) {
+	sort.SliceStable(ts, func(i, j int) bool {
+		return sb(&ts[i]) <= sb(&ts[j])
+	})
+}