环境 Python 3.6.3 + Pyforms 3.0.0
模拟：
内存管理模型的设计与实现
对内存的可变分区申请采用链表法管理进行模拟实现。要求：
设计思想
约定内存页数为16（索引地址为0-15），进程用字典表示，键是进程的标识符，值是进程的起始地址和占用内存页数。
每当有新的进程申请，检测内存中是否有足够的剩余空间，若没有，则紧缩内存，再次检查，若还是没有空间则输出失败信息；若有，根据选择的算法进行内存空间分配
变量和方法
主要变量：
self.lastAddress 记录上一次分配的内存地址，用于邻近适度算法。
self.processes 记录进程信息，包括进程的进程名、起始地址和大小。
主要方法：
getEmptyBlocks 获取空闲区域的起始地址和大小，函数会遍历整个内存，记录连续出现的‘N’（表示该页空闲）的位置和长度。
tightening 紧缩内存空间，从内存索引为0开始重新赋予进程起始地址，并根据起始地址更新GUI。
apply 申请进程，从GUI获取进程的名字和大小，检查内存剩余空间是否满足进程需求，满足需求时根据不同算法调度内存空间。算法见下：
首次适度算法：从头遍历getEmptyBlocks返回的记录（数据类型为列表），找到第一个满足要求的索引，从该索引更新进程信息。
最优适度算法：从getEmptyBlocks返回的数据中减去进程需求，找到最小值对应的索引，从该索引更新进程信息。
邻近适度算法，遍历getEmptyBlocks返回的数据，第一次从索引大于self.lastAddress的索引中查找满足条件的索引，若找到，从该索引更新进程信息；否则，从头开始查找。
运行截图
程序初始化
第一行表示内存页地址
第二行表示该页是否为空（N表示空）
分别申请进程名为a、b、c、d、e，内存大小都为3的进程，算法使用首次适度算法
查询内存使用状态
撤销进程a、b、d，采用最优适度算法申请大小为3的进程f
重置内存，分别申请进程名为a、b、c的3个进程，进程大小都为3，采用首次适度算法
撤销进程a，采用邻近适度算法申请大小为3的进程d
通过内存紧缩，申请大小为6的进程e
查询内存使用状态
import pyforms from pyforms import BaseWidget from pyforms.controls import * class Memory(BaseWidget): def __init__(self): super(Memory, self).__init__("内存分配模拟器") # 进程字典 # 键值对为编号和实例 self.processes = dict() # GUI # 查询页 self.textArea = ControlTextArea('内存使用情况') # 管理页 # 第一行 内存地址 self.memoryMark_0 = ControlLabel('0') self.memoryMark_1 = ControlLabel('1') self.memoryMark_2 = ControlLabel('2') self.memoryMark_3 = ControlLabel('3') self.memoryMark_4 = ControlLabel('4') self.memoryMark_5 = ControlLabel('5') self.memoryMark_6 = ControlLabel('6') self.memoryMark_7 = ControlLabel('7') self.memoryMark_8 = ControlLabel('8') self.memoryMark_9 = ControlLabel('9') self.memoryMark_10 = ControlLabel('10') self.memoryMark_11 = ControlLabel('11') self.memoryMark_12 = ControlLabel('12') self.memoryMark_13 = ControlLabel('13') self.memoryMark_14 = ControlLabel('14') self.memoryMark_15 = ControlLabel('15') # 第二行 内存使用进程标记 self.memoryUser_0 = ControlLabel('') self.memoryUser_1 = ControlLabel('') self.memoryUser_2 = ControlLabel('') self.memoryUser_3 = ControlLabel('') self.memoryUser_4 = ControlLabel('') self.memoryUser_5 = ControlLabel('') self.memoryUser_6 = ControlLabel('') self.memoryUser_7 = ControlLabel('') self.memoryUser_8 = ControlLabel('') self.memoryUser_9 = ControlLabel('') self.memoryUser_10 = ControlLabel('') self.memoryUser_11 = ControlLabel('') self.memoryUser_12 = ControlLabel('') self.memoryUser_13 = ControlLabel('') self.memoryUser_14 = ControlLabel('') self.memoryUser_15 = ControlLabel('') self.memoryUser = [self.memoryUser_0, self.memoryUser_1, self.memoryUser_2, self.memoryUser_3, self.memoryUser_4, self.memoryUser_5, self.memoryUser_6, self.memoryUser_7, self.memoryUser_8, self.memoryUser_9, self.memoryUser_10, self.memoryUser_11, self.memoryUser_12, self.memoryUser_13, self.memoryUser_14, self.memoryUser_15 ] self.memoryUserMark = [False] * 16 for i in self.memoryUser: i.value = 'N' # 第三行 进程申请内存 self.applyLabel = ControlLabel('进程申请') self.applyName = ControlText('进程名') self.applySpace = ControlText('申请内存大小') self.applyBtn = ControlButton('申请') # 第四行 进程撤销 self.deleteLabel = ControlLabel('进程撤销') self.deleteName = ControlText('进程名') self.deleteBtn = ControlButton('撤销') # 第五行 算法选择 self.algorithm = ControlCombo('算法选择') self.algorithm.add_item('首次适度算法', 0) self.algorithm.add_item('最优适度算法', 1) self.algorithm.add_item('邻近适度算法', 2) # 第六行 查询和重置 self.query = ControlButton('查询') self.reset = ControlButton('重置') # 绑定按钮和事件 self.applyBtn.value = self.apply self.deleteBtn.value = self.delete self.query.value = self.query_s self.reset.value = self.setMemoryEmpty # GUI布局 self.formset = [{ '管理': [( 'memoryMark_0', 'memoryMark_1', 'memoryMark_2', 'memoryMark_3', 'memoryMark_4', 'memoryMark_5', 'memoryMark_6', 'memoryMark_7', 'memoryMark_8', 'memoryMark_9', 'memoryMark_10', 'memoryMark_11', 'memoryMark_12', 'memoryMark_13', 'memoryMark_14', 'memoryMark_15' ), ( 'memoryUser_0', 'memoryUser_1', 'memoryUser_2', 'memoryUser_3', 'memoryUser_4', 'memoryUser_5', 'memoryUser_6', 'memoryUser_7', 'memoryUser_8', 'memoryUser_9', 'memoryUser_10', 'memoryUser_11', 'memoryUser_12', 'memoryUser_13', 'memoryUser_14', 'memoryUser_15', ), ('applyLabel', 'applyName', 'applySpace', 'applyBtn'), ('deleteLabel', 'deleteName', 'deleteBtn'), ('algorithm'), ('query', 'reset') ], '查询':['textArea'] }] # 上次分配地址 self.lastAddress = 0 # 获取空闲内存页 def getEmptyBlocks(self): blocks = list() i = 0 while i < 16: if self.memoryUser[i].value == 'N': size = 1 blocks.append(i) while i < 15: i += 1 if self.memoryUser[i].value == 'N': size += 1 else: blocks.append(size) break i += 1 if len(blocks) & 1 == 1: temp = blocks[len(blocks)-1] blocks.append(16-temp) return blocks # 用进程名更新进程占用的内存页 def changeMemory(self, name, index, size): for i in range(index, index+size): self.memoryUser[i].value = name # 撤销进程后重置对应内存页为空 def resetMemory(self, index, size): for i in range(index, index+size): self.memoryUser[i].value = 'N' # 重置数据为空 def setMemoryEmpty(self): for i in range(16): self.memoryUser[i].value = 'N' self.processes = dict() self.lastAddress = 0 # 紧缩 def tightening(self): for i in range(16): self.memoryUser[i].value = 'N' lastIndex = 0 for i in self.processes: process = self.processes[i] process[0] = lastIndex self.changeMemory(i, process[0], process[1]) self.lastAddress = lastIndex lastIndex += process[1] # 进程申请 def apply(self): blocks = self.getEmptyBlocks() index = list() size = list() for i in range(int(len(blocks)/2)): index.append(blocks[i*2]) size.append(blocks[i*2+1]) need = int(self.applySpace.value) name = self.applyName.value # 若剩余空间不满足申请要求则紧缩 if need > max(size): self.tightening() # 在紧缩的基础上若剩余空间不满足申请要求则输出失败信息 blocks = self.getEmptyBlocks() index = list() size = list() for i in range(int(len(blocks)/2)): index.append(blocks[i*2]) size.append(blocks[i*2+1]) need = int(self.applySpace.value) name = self.applyName.value if need > max(size): s = '进程' s += name s += '申请失败\n' s += '当前最大空闲区域页数为' s += str(max(size)) self.textArea.value = s # 若满足申请要求则根据选择的算法进行分配 else: # 首次适度算法 if self.algorithm.value == 0: for i in range(len(index)): if need <= size[i]: self.changeMemory(name, index[i], need) self.processes[name] = [index[i], need] self.lastAddress = index[i] break # 最优适度算法 elif self.algorithm.value == 1: bestSize = [i - need for i in size] size = [] for i in bestSize: if i >= 0: size.append(i) bestIndex = 0 bestMin = 16 for i in range(len(size)): if bestMin > size[i]: bestMin = size[i] bestIndex = i self.changeMemory(name, index[bestIndex], need) self.processes[name] = [index[bestIndex], need] self.lastAddress = index[bestIndex] # 邻近适度算法 else: compare = self.lastAddress for i in range(len(index)): if compare <= index[i] and need <= size[i]: self.changeMemory(name, index[i], need) self.processes[name] = [index[i], need] self.lastAddress = index[i] return for i in range(len(index)): if need <= size[i]: self.changeMemory(name, index[i], need) self.processes[name] = [index[i], need] self.lastAddress = index[i] # 进程撤销 def delete(self): name = self.deleteName.value if name in self.processes: process = self.processes[name] del self.processes[name] self.resetMemory(process[0], process[1]) # 查询 def query_s(self): showValue = '' for i in self.processes: process = self.processes[i] s = '进程名：' + i s += '\t起始地址:' s += str(process[0]) s += '\t进程大小:' s += str(process[1]) s += '\n' showValue += s self.textArea.value = showValue if __name__ == "__main__": pyforms.start_app(Memory)文章来源: Pyforms 模拟内存管理模型