On Tue, 17 Jan 2006, Joachim Schipper wrote:
> On Tue, Jan 17, 2006 at 02:15:57PM +0100, Otto Moerbeek wrote:
>
> > You are wrong in thinking sparse files are a problem. Having sparse
> > files quite a nifty feature, I would say.
>
> Are we talking about webazolver or OpenBSD?
>
> I'd argue that relying on the OS handling sparse files this way instead
> of handling your own log data in an efficient way *is* a problem, as
> evidenced by Daniels post. After all, it's reasonable to copy data to,
> say, a different drive and expect it to take about as much space as the
> original.
Now that's a wrong assumption. A file is a row of bytes. The only
thing I can assume is that if I write a byte at a certain position, I
will get the same byte back when reading the file. Furthermoe, the
file size (not the disk space used!) is the largest position written.
If I assume anything more, I'm assuming too much.
For an application, having sparse files is completely transparant. The
application doesn't even know the difference. How the OS stores the
file is up to the OS.
Again, assuming a copy of a file takes up as much space as the
original is wrong.
> On the other hand, I agree with you that handling sparse files
> efficiently is rather neat in an OS.
-Otto
