Re: Filesize limitation

Albert D. Cahalan (acahalan@cs.uml.edu)
Tue, 11 Nov 1997 01:55:09 -0500 (EST)


I wanted to understand ext2 limits better, so I graphed how
the maximum file size changes with block size. It even shows
where your performance drops as the filesystem starts to use
more indirect blocks. In case anybody is interested:

http://www.cs.uml.edu/~acahalan/ext2.gif

In both ways, the scale goes 1,2,4,8... bits. (log base 2)

The pink area is what I think ext2 could reasonably be extended to.
It would require support for block sizes from 512 bytes to 64 kB
and a 64-bit file offset.

I think the 64-bit API comes first. That would get 4 GB files
without much (any?) change to the main ext2 code.

I can't test any code; this is just very interesting for me.
If only I could buy an 11 TB disk cluster from EMC... :-)

Let me know of any errors in the graph.