Unix administration - Difference between bsize and frsize in statvfs?

Author

Difference between bsize and frsize in statvfs?

Subotai

2005-02-10, 2:48 am

Does anyone know what the difference between the bsize and frsize values in
the statvfs() call are? From various man pages on different flavors of Unix,
all I can gather is that frsize is the "fundamental filesystem block size"
and bsize is "preferred file system block size" Does anyone actually know
what this means?

I would assume that frsize would return the actual block size used by the
system. But I have found a cases where it doesn't and bsize does. I am not
sure if bsize always will contain the block size used by the system or not.

Does anyone know which value will absolutely hold the block size used by the
system?

Thanks