Sparse Allocation Over CIFS (Samba)?

[yottabit]

Hi Folks!

I have STF and even Google and come up without conclusive support of whether or not sparse allocation is supported over a mapped CIFS network share... any ideas? I know Samba does suppose sparse allocation (and it's on by default), but I haven't seen anything on the µTorrent forums or documentation that addresses this specific case.

Any ideas?

If no one knows I will try to come up with a test scenario to check it myself using Linux dd and µTorrent over CIFS while downloading OpenOffice to compare.

Edit:

Okay I guess that didn't take as long as I was fearing. First I used a win32 version of dd to create a sparse file over the CIFS mount:

C:\Junk>.\dd if=/dev/zero of=n:\Junk\dd_win32_test bs=1 count=1 seek=1G
rawwrite dd for windows version 0.5.
Written by John Newbigin <jn@it.swin.edu.au>
This program is covered by the GPL.  See copying.txt for details
1+0 records in
1+0 records out

And I checked it from the NAS which is actually OpenFiler using CIFS to an XFS filesystem:

[root@nas1 Junk]# ls -lh dd_win32_test
-rwxrwx---  1 zaphod mcdtech 1.1G Oct 29 23:04 dd_win32_test
[root@nas1 Junk]# du -ch dd_win32_test
8.0K    dd_win32_test
8.0K    total

Next I made sure the sparse option was true in µTorrent and started up an OOo torrent. I pause it as soon as I saw activity and did this:

[root@nas1 Incomplete]# ls -lh OOo_3.1.1_Win32Intel_install_wJRE_en-US.exe.\!ut
-rwxrwx---  1 zaphod mcdtech 151M Oct 29 23:07 OOo_3.1.1_Win32Intel_install_wJRE_en-US.exe.!ut
[root@nas1 Incomplete]# du -ch OOo_3.1.1_Win32Intel_install_wJRE_en-US.exe.\!ut
644K    OOo_3.1.1_Win32Intel_install_wJRE_en-US.exe.!ut
644K    total

Conclusion? µTorrent rocks of course! But seriously... I could have saved myself time by just trying out the OOo torrent first and not bothering with dd. haha.

Sparse files are done automagically at least over CIFS to a NAS box running the XFS filesystem.

Thanks again to the wonderful programmers of µTorrent. Best. Torrent. App. Ever.

[Ultima]

Cool Still, I would think it's Windows that's correctly handing the sparse file flag over to the networked drive, as the fact that it's a networked drive should pretty much be abstracted away from µTorrent. I could be wrong, of course.