AIX

Hi Guys,

I have this filesystem got big with inode:

/dev/hd4 3670016 183664 95% 63705 58% /var

I don't know why the system doesn't give alerts on this FS although it's 95% and why the inode is 58%.

Any comments will be highly appreciated.

Thanks,
itik

The OS wont give you any alerts, regardless of how much filled a filesystem is. If you have some monitoring software, which does that for you (Patrol, HP/OpenView, CA-Unicenter, ....) then perhaps this software (more precisely: probably its agent) is at fault.

Every filesystem is a collection of disk space units - blocks, usually 512 bytes in size - which can be used by a file or be free. The ratio of used to unused blocks is what makes the filling percentage of the filesystem. "95%" means out of every 100 blocks 95 are used.

So far, so simple. But there is another side to it: whenever you create a file one special bookkeeping entry is being created - the inode. Inodes contain the information you see when you issue an "ls" - filename, modifikation date, size, etc.. Inodes are stored in a special part of the filesystem, which has to be set aside when the filesystem is being created.Your number of 58% says that of these inodes 58% are being used.

The ratio of inodes to available raw space is not fixed - when creating a filesystem there is an attribute "nbpi" - "number of bytes per inode". You can tune this number to fit your purposes: The default is good for the "usual mix" of files, but if you know that the filesystem will hold many small files you might wat to increase the number of inodes, otherwise you might run into the situation where you still have space left on the disk but have no inodes left to create files and use that space.

On the other hand, if you know that the FS will contain very few very large files (best example: databases) you can decrease the number of inodes to make more diskspace available for storage purposes.

bakunin