Create new files as sparse on NT systems. (2nd try)
Gary R Van Sickle
Tue Feb 18 22:59:00 GMT 2003
> >What kind of program would actually benefit from sparse
> files? And shouldn't
> >it be the responsibility of that program to request them?
> IIRC, linux creates sparse files automatically when you do an lseek to
> a position beyond EOF. I believe that Windows is similar.
No, Windows does nothing like that. On Windows, sparse files are completely
"Note: It is up to the application to maintain sparseness by writing zeros
with FSCTL_SET_ZERO_DATA", sez the Platform docs.
Even if you do WriteFile()s with all zeros on a sparse file, you are
actually hitting the disk.
> I would like to see a benchmark but I doubt there will be any
The only thing this patch will do AFAICS is set a bit somewhere in the guts
of NTFS that will be pretty much ignored. I'm with Max, I don't see the
benefit and can only imagine the consequences.
Gary R. Van Sickle
11481 Rupp Dr.
Burnsville, MN 55337
More information about the Cygwin-patches