SPARSE files considered harmful - please revert

[Rolf Campbell]

Max Bowsher wrote:

> Martin Buchholz wrote:
> 
>>As a result, a non-empty but small sparse file takes up a minimum of
>>16*clustersize bytes on the disk.  My measurements suggest an overhead
>>of 32kb per file with a cluster size of 4kb.
> 
> 
> I just thought I'd throw a few more numbers into the debate:
> 
> I patched Cygwin to respond to CYGWIN=sparse / CYGWIN=nosparse
> Then, I did a cvs co winsup:
> 
> "Size on disc" of checked out dir, as shown in Windows properties box:
> Sparse: 40.7MB
> Not sparse: 43.6MB
> OK, so sparse seems to win? But that makes no sense - backed up by noting
> that for various individual sparse files, "Size on disc" is reporting a size
> which is not an integer number of clusters.
> 
> Now, Properties of disc, look at "Used space":
> Difference in creating sparse checkout: ~ 200MB !!!
> Difference in creating normal checkout: ~  40MB
> 
> Personally, I'm inclined to trust the overall disc stats more.
> 
> I think this evidence suggests that sparse files should NOT be on by default
> in Cygwin.

I just checked out a corporate build system, which had average file size 
much bigger.  It decreases the available disk space by 300Megs with 
non-sparce files, and 390Megs with sparce files.



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