[20210828]如何实现2.txt

来源：这里教程网时间：2026-03-03 16:54:22 作者：

[20210828]如何实现2.txt --//内核参数kernel.sem的探究,需要写一个命令,看看processes,nsems,semaphores_used_arrays的关系，自己看看如何实现. $ seq 196 1 204 | xargs -IQ echo "scale=0;Q;a=(Q+4)/4;scale=3;b=Q/(a-4);a;b" | bc | tr -d '\r' | paste - - - 196 50 4.260 197 50 4.282 198 50 4.304 199 50 4.326 200 51 4.255 201 51 4.276 202 51 4.297 203 51 4.319 204 52 4.250 --//以上按照2^2来分组的情况.最后一列输出使用ceil，就是对应semaphores arrays的数量。 --//写的更复杂一些，分析processes=196 ~ 204,分组 2^N (N=1,2,3,4)的情况。 $ seq 4 | xargs -IQ bash -c "seq 9 | xargs -iZ echo 'scale=0;c=2^Q'" $ seq 4 | xargs -IQ bash -c "seq 196 1 204 | xargs -IZ echo 'scale=0;a=(Z+4)/c;scale=3;b=Z/(a-4);Z;c;a;b;'" $ paste -d";" <(seq 4 | xargs -IQ bash -c "seq 9 | xargs -iZ echo 'scale=0;c=2^Q'" ) <(seq 4 | xargs -IQ bash -c "seq 196 1 204 | xargs -IZ echo 'scale=0;a=(Z+4)/c;scale=3;b=Z/(a-4);Z;c;a;b;'") | bc | tr -d "\r" | paste - - - - 196 2 100 2.041 197 2 100 2.052 198 2 101 2.041 199 2 101 2.051 200 2 102 2.040 201 2 102 2.051 202 2 103 2.040 203 2 103 2.050 204 2 104 2.040 196 4 50 4.260 197 4 50 4.282 198 4 50 4.304 199 4 50 4.326 200 4 51 4.255 201 4 51 4.276 202 4 51 4.297 203 4 51 4.319 204 4 52 4.250 196 8 25 9.333 197 8 25 9.380 198 8 25 9.428 199 8 25 9.476 200 8 25 9.523 201 8 25 9.571 202 8 25 9.619 203 8 25 9.666 204 8 26 9.272 196 16 12 24.500 197 16 12 24.625 198 16 12 24.750 199 16 12 24.875 200 16 12 25.000 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 201 16 12 25.125 202 16 12 25.250 203 16 12 25.375 204 16 13 22.666 --//说明:输出顺序 processes group nsems semaphores_used_arrays. --//随手写了一个类似的脚本，结果不贴出了。 seq 4 | xargs -IQ bash -c "seq 9 | xargs -iZ echo 'scale=0;c=Q'" seq 4 | xargs -IQ bash -c "seq 196 1 204 | xargs -IZ echo 'd=Z;'" paste -d";" <(seq 4 | xargs -IQ bash -c "seq 9 | xargs -iZ echo 'scale=0;c=Q'" ) <(seq 4 | xargs -IQ bash -c "seq 196 1 204 | xargs -IZ echo 'd=Z;'") paste -d";" <(seq 4 | xargs -IQ bash -c "seq 9 | xargs -iZ echo 'scale=0;c=Q'" ) <(seq 4 | xargs -IQ bash -c "seq 196 1 204 | xargs -IZ echo 'd=Z;'") | xargs -IY echo 'Ya=(d+4)/2^c;scale=3;b=d/(a-4);d;2^c;a;b;' | bc| tr -d '\r'| paste - - - - paste -d";" <(seq 4 | xargs -IQ bash -c "seq 9 | xargs -iZ echo 'scale=0;c=Q'" ) <(seq 4 | xargs -IQ bash -c "seq 196 1 204 | xargs -IZ echo 'd=Z;'") | xargs -IY echo 'Ya=(d+4)/2^c;scale=3;b=d/(a-4);print d," ",c," ",a," ",b,"\n"' | bc paste -d";" <(seq 4 | xargs -IQ bash -c "seq 9 | xargs -iZ echo 'scale=0;c=Q'" ) <(seq 4 | xargs -IQ bash -c "seq 196 1 204 | xargs -IZ echo 'd=Z;'") | xargs -IY echo 'Ya=(d+4)/2^c;scale=3;b=d/(a-4);print d,"\t",c,"\t",a,"\t",b,"\n"' | bc paste -d";" <(seq 4 | sed -n "p;p;p;p;p;p;p;p;p"| xargs -IQ echo 'scale=0;c=Q' ) <(seq 4 | xargs -IQ bash -c "seq 196 1 204 | xargs -IZ echo 'd=Z;'") | xargs -IY echo 'Ya=(d+4)/2^c;scale=3;b=d/(a-4);print d,"\t",c,"\t",a,"\t",b,"\n"' | bc