Bug 781866

Summary: Can't unmount NTFS volumes due to unknown write activity
Product: [Fedora] Fedora Reporter: James <fedorabugmail>
Component: ntfs-3gAssignee: Tom "spot" Callaway <tcallawa>
Status: CLOSED NOTABUG QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: medium Docs Contact:
Priority: unspecified    
Version: 16CC: jean-pierre.andre, tcallawa
Target Milestone: ---   
Target Release: ---   
Hardware: x86_64   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
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Clone Of: Environment:
Last Closed: 2012-01-19 16:11:05 UTC Type: ---
Regression: --- Mount Type: ---
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description James 2012-01-15 19:17:53 UTC 
This is on a system containing one drive with multiple partitions: Two for Win7 and two for Linux. After mounting one of the NTFS volume through the XFCE file manager, it is not possible to unmount the volume. Attempts to do so through the GUI gives a message indicating there are still active writes pending. Using umount also gives a similar error messages regarding pending writes. 

* A few seconds after mounting, I notice a large amount of disk activity(based on the hardware LED) and the file manager becomes very unresponsive.
* Using windows, it *appears* that no changes have been made to the NTFS volume
* When mounting a FAT32 external drive, none of this happens. Performance is consistently fast and the drive can be unmounted at any time.
Comment 1 Jean-Pierre André 2012-01-17 20:30:52 UTC 
> Attempts to do so through the GUI gives a message indicating
> there are still active writes pending. Using umount also
> gives a similar error messages regarding pending writes. 

What error message ?
The usual reason is that the process calling mount(8) has open files when mounting. The corresponding file descriptors are inherited by the fuse process, which do not know about them and cannot close them.

> A few seconds after mounting, I notice a large amount of disk
> activity(based on the hardware LED) and the file manager becomes
> very unresponsive.

This is for computing available disk space. This may be significant if the partition is big and is formatted with small clusters (4K recommended).

> When mounting a FAT32 external drive, none of this happens.
> Performance is consistently fast and the drive can be unmounted
> at any time.

The FAT file system is plugged within the kernel, hence it has no process inheriting open file descriptors. Computing free space depends on the number of clusters.
Comment 2 James 2012-01-19 16:11:05 UTC 
Not a bug with ntfs-3g. After several tries lsof was able to show 'tumblerd' was accessing the disk.