cylinder group size problem

[sundeep]

Hi all,

I am working on Solaris 8 . Its default file system is UFS. My problem is regarding to the file system. I create two partition 1) / 1.2 Gb and 2) /home 4.5 GB

In root partition there were 76 Cylinder groups ,when I was traversing the Cylinder Groups I found that the length of one cylinder Group was 32320 sector long. Up to 32 cylinder groups that length was absolutely fine ,when I jump to the 33rd Cyl. Grp. That difference reduces to 31296 sectors it means it reduces by 1024 sectors. And it happens at every multiple of 32 cylinder groups. Is there any information regarding this in SuperBlock or in Cylinder Summary Block Structure.

 

In 2nd case of /home partition there were 286 cyl. Grp. , the length of 1 Cylinder Group was 98848 , In this case also when I jump to 32nd  to 33rd  Cylinder Group the length reduces to 2048 sectors,It means length becomes 96800 sectors. It happens every multiple of 32 means 64th to 65th , 96th to 97th like this. 

This difference usually came when I create a  big partitions but when I create 1 gb partition then this difference became 1024 sectors.

Please help me to solve this problem how can I got this value or is there any formula.

I am also not getting the structure of "cylinder group summary area" its address is defined in Superblock structure.

With Thanks and Regards

 

Sundeep Saini