Python实现处理机和进程调度算法及内存分配回收机制源码+项目说明+代码注释(附Vue前端源码).zip

from proc.Config import Memory, OSMemory from proc.EnumClass import PCBState, MemoryBlockState, Property, MemoryBlockStateDict from proc.PCB import PCB from proc.PCBQueue import PCBQueue from proc.Processor import Processor class MainMemory: def __init__(self): self.__readyList = [] # 有序分区表[[PID, 起址, 长度, 状态], ...]，按起始地址进行升序排序 # 内存分区表中对应存储的PID，OS对应的内存表项用-1表示，未分配内存表项用-2表示 self.__memory = [[-1, 0, OSMemory, MemoryBlockState.OS_ASSIGNED], [-2, OSMemory, Memory - OSMemory, MemoryBlockState.UNASSIGNED]] # self.__memoryPCB = [-1, -2] def toJson(self): jsonList = [] for index, memoryBlock in enumerate(self.__memory): jsonList.append({ 'memory_PCB': memoryBlock[0], 'start': memoryBlock[1], 'length': memoryBlock[2], 'memory_state': MemoryBlockStateDict[memoryBlock[3].name], }) return {'main_memory': jsonList} def checkAssignable(self, pcb: PCB): # 检测是否可分配空间，同时返回可分配内存空间的起始地址 for index, memoryBlock in enumerate(self.__memory): if memoryBlock[3] == MemoryBlockState.UNASSIGNED and memoryBlock[2] >= pcb.getRam(): return True, index # memoryBlockNum = index return False, -1 def insertPCB(self, pcb: PCB, memoryBlockNum: int): # 将进程插入内存之前需要先调用checkAssignable()检查是否可分配空间 partition = self.__memory[memoryBlockNum] pcb_ram = pcb.getRam() pcb_id = pcb.getPID() self.__readyList.append(pcb_id) pcb.setState(PCBState.ACTIVE_READY) if partition[2] == pcb_ram: # 内存长度正好相等 partition[0] = pcb_id partition[3] = MemoryBlockState.ASSIGNED else: self.__memory.insert(memoryBlockNum + 1, [-2, partition[1] + pcb_ram, partition[2] - pcb_ram, MemoryBlockState.UNASSIGNED]) partition[0] = pcb_id partition[2] = pcb_ram partition[3] = MemoryBlockState.ASSIGNED def checkProcessable(self, pcb_queue: PCBQueue, processor: Processor): if len(self.__readyList) > 0: # 内存中有进程 for l in processor.getProcessorPCBList(): for pid in l: # 处理机中有独立进程，或前驱已经结束的同步进程 pcb = pcb_queue.getPCBByPID(pid) if pcb.getProperty() == Property.INDEPENDENT: return True # 独立进程 else: # 同步进程 precursorList = pcb.getPrecursor() preExitList = [pcb_queue.getPCBByPID(i).getState() == PCBState.EXIT for i in precursorList] if sum(preExitList) == len(preExitList): return True # preExitList中全部为True，前驱进程全部完成 return False def process(self, pcb_queue: PCBQueue, processor: Processor): # 处理机运行程序 processor.process(pcb_queue) # 在Processor.process()后执行，用于清除内存中已经结束的进程，并合并未分配内存空间 PCBToRemoveList = [] for partition in self.__memory: pid = partition[0] if pid >= 0 and pcb_queue.getPCBByPID(pid).getState() == PCBState.EXIT: # 如果内存中存在结束进程 PCBToRemoveList.append(pid) if PCBToRemoveList: for pid in PCBToRemoveList: self.removePCB(pcb_queue.getPCBByPID(pid), processor) def removePCB(self, pcb: PCB, processor: Processor): # 从处理机中移除PCB isRemoved = processor.removePCB(pcb) # 从内存中移除PCB memoryBlockNum = 0 pid = pcb.getPID() for index, value in enumerate(self.__memory): if value[0] == pid: memoryBlockNum = index self.__readyList.remove(pid) self.__memory[memoryBlockNum][0] = -2 self.__memory[memoryBlockNum][3] = MemoryBlockState.UNASSIGNED self.__mergeMemory() def __mergeMemory(self): # 合并未分配的内存空间 flag = False memoryBlockToMergeList = [] # 记录要合并的第二块及其后内存块的位置 for index, value in enumerate(self.__memory): pid = value[0] if pid == -2: # 检测到未分配的内存空间（-2） if not flag: # 第一次检测到未分配的内存空间（-2） flag = True else: # 不是第一次检测到未分配的内存空间（-2），即有连续的未分配空间 memoryBlockToMergeList.append(index) if pid != -2: # 检测到已分配的内存空间（!=-2） flag = False if memoryBlockToMergeList: beginMemoryBlockNum = memoryBlockToMergeList[0] - 1 # 要合并的第一个内存块的位置 for partition in memoryBlockToMergeList[::-1]: memoryBlockToMerge = self.__memory.pop(partition) # 倒序pop self.__memory[beginMemoryBlockNum][2] += memoryBlockToMerge[2] def dispatchProcessor(self, pcb_queue: PCBQueue, processor: Processor): # 对内存空间中（处于就绪队列中）的进程按抢占式优先权调度算法安排调度 # 首先将独立进程，以及前驱已经完成的同步进程按优先权降序加入列表 # 然后将同步进程按优先权降序加入列表 # 最后为进程分配处理机 freePIDDic = {} # 独立进程，以及前驱已经完成的同步进程 syncPIDDic = {} # 同步进程 for i in self.__readyList: pcb = pcb_queue.getPCBByPID(i) # 每个处理机中的进程状态设置为PCBState.ACTIVE_READY pcb.setState(PCBState.ACTIVE_READY) if pcb.getProperty() == Property.INDEPENDENT: # 独立进程 freePIDDic[i] = pcb.getPriority() else: precursorList = pcb.getPrecursor() preExitList = [pcb_queue.getPCBByPID(i).getState() == PCBState.EXIT for i in precursorList] if sum(preExitList) == len(preExitList): # preExitList中全部为True，前驱进程全部完成 freePIDDic[i] = pcb.getPriority() else: # 同步进程 syncPIDDic[i] = pcb.getPriority() sortedFreeList = sorted(freePIDDic.items(), key=lambda item: item[1], reverse=True) # 按优先权降序排序 sortedSyncList = sorted(syncPIDDic.items(), key=lambda item: item[1], reverse=True) # 按优先权降序排序 sortedList = sortedFreeList + sortedSyncList processor.dispatchPCB(sortedList)