sparse files

[Mike Reinehr]

On Tuesday 24 May 2005 01:20 am, Roger Oberholtzer wrote:
> On Sat, 2005-05-21 at 12:37 +0800, Man-wai Chang wrote:
> > > Next I wanted to copy the image to another computer. So, I thought I
> > > would use tar's --sparse option to make a file to copy, and then untar
> > > it and have the sparse file on the other computer. Nope. The untarred
> > > file stops at 2GB. So, I thought I had some file size limit. So, I
> > > tried
> >
> > What file system does your target system use?
>
> Same as the source - ext3.
>
> The sparse file is not re-created correctly on the same system the
> original sparse file exists. The odd thing is that if the original
> sparse file contains, say, 500MB of actual content in a 6GB sparse file,
> the recreated sparse file is always 2 GB. Could it be that there is a
> 2GB limit on the ext3 file system that does not apply to sparse files? I
> wonder what would happen if I tried to fill the sparse file with more
> than 2GB of content. I also need to check if the file created by tar is
> really sparse. Anyone know how to fine how much space is really used in
> a sparse file?
>
> What confuses me is that all the discussions of this are joyous about
> how well tar does this. Many predate the newer file systems, so I guess
> they are for ext2/3 file systems. Sadly they seldom tell.
>
> I will experiment a bit more.

Roger,

Try the `ulimit` command to see if you are working under any resource limits: 
http://www.linuxcommand.org/man_pages/ulimit1.html

cmr
-- 
Debian 'Sarge': Registered Linux User #241964

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