#region License Information /* HeuristicLab * Copyright (C) 2002-2015 Heuristic and Evolutionary Algorithms Laboratory (HEAL) * * This file is part of HeuristicLab. * * HeuristicLab is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * HeuristicLab is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with HeuristicLab. If not, see . */ #endregion using System; using System.Collections.Generic; using System.Linq; using HeuristicLab.Services.Hive.DataAccess.Interfaces; using DA = HeuristicLab.Services.Hive.DataAccess; namespace HeuristicLab.Services.Hive { public class RoundRobinTaskScheduler : ITaskScheduler { private IPersistenceManager PersistenceManager { get { return ServiceLocator.Instance.PersistenceManager; } } public IEnumerable Schedule(IEnumerable tasks, int count = 1) { if (!tasks.Any()) return Enumerable.Empty(); var pm = PersistenceManager; var userPriorityDao = pm.UserPriorityDao; var jobDao = pm.JobDao; var userPriorities = pm.UseTransaction(() => userPriorityDao.GetAll() .OrderBy(x => x.DateEnqueued) .ToArray() ); var userIds = userPriorities.Select(x => x.UserId).ToList(); var jobs = pm.UseTransaction(() => { return jobDao.GetAll() .Where(x => userIds.Contains(x.OwnerUserId)) .Select(x => new { Id = x.JobId, DateCreated = x.DateCreated, OwnerUserId = x.OwnerUserId }) .ToList(); }); var taskJobRelations = tasks.Join(jobs, task => task.JobId, job => job.Id, (task, job) => new { Task = task, JobInfo = job }) .OrderByDescending(x => x.Task.Priority) .ToList(); var scheduledTasks = new List(); int priorityIndex = 0; if (count == 0 || count > taskJobRelations.Count) count = taskJobRelations.Count; for (int i = 0; i < count; i++) { var defaultEntry = taskJobRelations.First(); // search first task which is not included yet var priorityEntries = taskJobRelations.Where(x => x.JobInfo.OwnerUserId == userPriorities[priorityIndex].UserId).ToArray(); // search for tasks with desired user priority while (!priorityEntries.Any() && priorityIndex < userPriorities.Length - 1) { priorityIndex++; priorityEntries = taskJobRelations.Where(x => x.JobInfo.OwnerUserId == userPriorities[priorityIndex].UserId).ToArray(); } if (priorityEntries.Any()) { // tasks with desired user priority found var priorityEntry = priorityEntries.OrderByDescending(x => x.Task.Priority).ThenBy(x => x.JobInfo.DateCreated).First(); if (defaultEntry.Task.Priority <= priorityEntry.Task.Priority) { taskJobRelations.Remove(priorityEntry); scheduledTasks.Add(priorityEntry.Task); UpdateUserPriority(pm, userPriorities[priorityIndex]); priorityIndex++; } else { // there are other tasks with higher priorities taskJobRelations.Remove(defaultEntry); scheduledTasks.Add(defaultEntry.Task); } } else { taskJobRelations.Remove(defaultEntry); scheduledTasks.Add(defaultEntry.Task); } if (priorityIndex >= (userPriorities.Length - 1)) priorityIndex = 0; } return scheduledTasks; } private void UpdateUserPriority(IPersistenceManager pm, DA.UserPriority up) { pm.UseTransaction(() => { up.DateEnqueued = DateTime.Now; pm.SubmitChanges(); }); } } }