存储管理的页面置换算法.doc

FCFS算法设计说明：按照所要求的产生随机指令序列，存放在order320这个数组中。通过循环产生这些随机指令，每产生一条都要进行下列判断：是否和内存中即mem_volume4中存放的页面相同，如果相同则不做任何操作，如果不相同，则产生缺页，相应的缺页次数加一，按照fcfs将最先进入内存的页数淘汰，并将该页写到内存中去。重复上面的操作直到完成这320条指令。Fcfs页面置换算法实现代码：#include #include #include int main(void)int order320,mem_volume4=100,100,100,100;int l=0,i=0,j,num=0,cx,sign=0,add=0;float value=0,sum=0;srand(time(NULL);for(cx=0;cx10;cx+)while(i320)orderi=rand()%320; /产生随机数放order中for(j=0;j4;j+)if(orderi+1)/10=mem_volumej)sign=1;/通过sign标识判断所调页数是否在内存块中if(sign)sign=0;elsel+;if(mem_volume3=100)mem_volume3=(orderi+1)/10;/ 保证第一次调入的页面都产生缺页elsemem_volumenum=(orderi+1)/10; /将所缺页调入到内存块中num=(num+1)%4; /num值为下次所要置换出去的内存块中对应的页数i+;orderi=rand()%(orderi-1+2);for(j=0;j4;j+)if(orderi/10=mem_volumej)sign=1;if(sign)sign=0;else l+;if(mem_volume2=100)mem_volume2=orderi/10;elsemem_volumenum=orderi/10;num=(num+1)%4;i+;orderi=orderi-1+1;for(j=0;j4;j+)if(orderi/10= mem_volumej)sign=1;if(sign)sign=0;elsel+;if(mem_volume1=100)mem_volume1=orderi/10;elsemem_volumenum=orderi/10;num=(num+1)%4; i+;orderi=rand()%(319-orderi-1-2)+(orderi-1+2);for(j=0;j4;j+)if(orderi/10=mem_volume0)sign=1;if(sign)sign=0;else l+;if(mem_volume0=100)mem_volume0=(orderi+1)/10;elsemem_volumenum=orderi/10;num=(num+1)%4; i+;value=l/320.0*100;add=add+l;sum=sum+value;printf(2*FCFS页面置换算法*2n);printf(*最后一次指令序列*);for(i=0;i320;i+)if(i%10=0)printf(n);printf(%5d,orderi);printf(n);printf(*n);printf(tt十次的平均缺页数为%dntt十次的平均缺页率为%.3f%,add/10,sum/10);return 0;LRU页面置换算法设计说明：这个算法同FCFS算法的不同之处在于，每产生一条随机指令，如果和4个内存块中的某一个页数相同的话，就要对这4个内存块中的页数重新排序，将每次要置换出去的页数放在mem_volume3中，这样，在每次产生缺页的时候，都先将所缺页数写入到该内存块，然后再排序，将其放到mem_volume0中去。LRU页面置换算法实现代码：#include #include #include int main(void)int order320,mem_volume4=100,100,100,100;int l=0,i=0,j,cx;int num,temp=0,ex_chan=0,add=0;float value=0,sum=0;srand(time(NULL);for(cx=0;cx10;cx+)while(i0;j-)temp=mem_volumej;mem_volumej=mem_volumej-1;mem_volumej-1=temp;else if(orderi+1)/10=mem_volume3)for(j=3;j0;j-)temp=mem_volumej;mem_volumej=mem_volumej-1;mem_volumej-1=temp; /如果所调页数同第3、4个内存块中页数相同，则通过循环进行排序elsel+;if(mem_volume3=100)mem_volume3=(orderi+1)/10;/保证刚开始调入内存块中就产生缺页elsemem_volume3=(orderi+1)/10;for(num=3;num0;num-)ex_chan=mem_volumenum;mem_volumenum=mem_volumenum-1;mem_volumenum-1=ex_chan;/写人后重新排序i+;orderi=rand()%(orderi-1+2);if(orderi/10=mem_volume0);else if(orderi/10=mem_volume1)temp=mem_volume1;mem_volume1=mem_volume0;mem_volume0=temp;else if(orderi/10=mem_volume2)for(j=2;j0;j-)temp=mem_volumej;mem_volumej=mem_volumej-1;mem_volumej-1=temp;else if(orderi/10 = mem_volume3)for(j=3;j0;j-)temp=mem_volumej;mem_volumej=mem_volumej-1;mem_volumej-1=temp;else l+;if(mem_volume2=100)mem_volume2=orderi/10;elsemem_volume3=orderi/10;for(num=3;num0;num-)ex_chan=mem_volumenum;mem_volumenum=mem_volumenum-1;mem_volumenum-1=ex_chan;i+;orderi=orderi-1+1;if(orderi/10= mem_volume0);else if(orderi/10 = mem_volume1)temp=mem_volume1;mem_volume1=mem_volume0;mem_volume0=temp;else if(orderi/10 = mem_volume2)for(j=2;j0;j-)temp=mem_volumej;mem_volumej=mem_volumej-1;mem_volumej-1=temp;else if(orderi/10=mem_volume3)for(j=3;j0;j-)temp=mem_volumej;mem_volumej=mem_volumej-1;mem_volumej-1=temp;elsel+;if(mem_volume1=100)mem_volume1=orderi/10;elsemem_volume3=orderi/10;for(num=3;num0;num-)ex_chan=mem_volumenum;mem_volumenum=mem_volumenum-1;mem_volumenum-1=ex_chan;i+;orderi=rand()%(319-orderi-1-2)+(orderi-1+2);if(orderi/10=mem_volume0);else if(orderi/10=mem_volume1)temp=mem_volume1;mem_volume1=mem_volume0;mem_volume0=temp;else if(orderi/10=mem_volume2)for(j=2;j0;j-)temp=mem_volumej;mem_volumej=mem_volumej-1;mem_volumej-1=temp;else if(orderi/10= mem_volume3)for(j=3;j0;j-)temp=mem_volumej;mem_volumej=mem_volumej-1;mem_volumej-1=temp;else l+;if(mem_volume0=100)mem_volume0=orderi/10;elsemem_volume3=orderi/10;for(num=3;num0;num-)ex_chan=mem_volumenum;mem_volumenum=mem_volumenum-1;mem_volumenum-1=ex_chan;i+;value=l/320.0*100;sum=sum+value;add=add+l;printf(2*LRU页面置换算法*2n);printf(*指令序列*);for(i=0;i320;i+)if(i%10=0)printf(n);printf(%5d,orderi);printf(n);printf(*n);printf(tt十次的平均缺页数为%dntt十次的平均缺页率为%.3f%,add/10,sum/10);return 0;LRU页面置换算法设计说明：这个算法同FCFS算法的不同之处在于，每产生一条随机指令，如果和4个内存块中的某一个页数相同的话，就要对这4个内存块中的页数重新排序，将每次要置换出去的页数放在mem_volume3中，这样，在每次产生缺页的时候，都先将所缺页数写入到该内存块，然后再排序，将其放到mem_volume0中去。LRU页面置换算法实现代码：#include #include #include int main(void)int order320,mem_volume4=100,100,100,100;int l=0,i=0,j,cx;int num,temp=0,ex_chan=0,add=0;float value=0,sum=0;srand(time(NULL);for(cx=0;cx10;cx+)while(i0;j-)temp=mem_volumej;mem_volumej=mem_volumej-1;mem_volumej-1=temp;else if(orderi+1)/10=mem_volume3)for(j=3;j0;j-)temp=mem_volumej;mem_volumej=mem_volumej-1;mem_volumej-1=temp; /如果所调页数同第3、4个内存块中页数相同，则通过循环进行排序elsel+;if(mem_volume3=100)mem_volume3=(orderi+1)/10;/保证刚开始调入内存块中就产生缺页elsemem_volume3=(orderi+1)/10;for(num=3;num0;num-)ex_chan=mem_volumenum;mem_volumenum=mem_volumenum-1;mem_volumenum-1=ex_chan;/写人后重新排序i+;orderi=rand()%(orderi-1+2);if(orderi/10=mem_volume0);else if(orderi/10=mem_volume1)temp=mem_volume1;mem_volume1=mem_volume0;mem_volume0=temp;else if(orderi/10=mem_volume2)for(j=2;j0;j-)temp=mem_volumej;mem_volumej=mem_volumej-1;mem_volumej-1=temp;else if(orderi/10 = mem_volume3)for(j=3;j0;j-)temp=mem_volumej;mem_volumej=mem_volumej-1;mem_volumej-1=temp;else l+;if(mem_volume2=100)mem_volume2=orderi/10;elsemem_volume3=orderi/10;for(num=3;num0;num-)ex_chan=mem_volumenum;mem_volumenum=mem_volumenum-1;mem_volumenum-1=ex_chan;i+;orderi=orderi-1+1;if(orderi/10= mem_volume0);else if(orderi/10 = mem_volume1)temp=mem_volume1;mem_volume1=mem_volume0;mem_volume0=temp;else if(orderi/10 = mem_volume2)for(j=2;j0;j-)temp=mem_volumej;mem_volumej=mem_volumej-1;mem_volumej-1=temp;else if(orderi/10=mem_volume3)for(j=3;j0;j-)temp=mem_volumej;mem_volumej=mem_volumej-1;mem_volumej-1=temp;elsel+;if(mem_volume1=100)mem_volume1=orderi/10;elsemem_volume3=orderi/10;for(num=3;num0;num-)ex_chan=mem_volumenum;mem_volumenum=mem_volumenum-1;mem_volumenum-1=ex_chan;i+;orderi=rand()%(319-orderi-1-2)+(orderi-1+2);if(orderi/10=mem_volume0);else if(orderi/10=mem_volume1)t