NTFS-3G Read/Write Driver Quality

NTFS-3G Quality

Reliability is the highest priority for the project. Great effort is devoted to careful engineering and permanent attention to ensure file and file system consistency in every conceivable situation.

Continuous quality testing and assurance is dominant part of the driver development. Additionally, each public release is preceded by an extensive, many hour long lasting functional, stability, interoperability, reliability and stress tests. No driver is ever released to the public with known defects which could cause data loss. The functionality limitations are also all documented before each release.

Test Methods

The following list describes the methods, tools, test suites which are used regularly and before each driver release.

Several NTFS utilities were developed over the past years to facilitate faster and reliable NTFS driver development and testing. The following tools are also tested because they are intensively used as part of many other tests, so it is crucial that they can be trusted.

Mkntfs validation on the bit and Windows FORMAT conformance level for all possible cluster sizes, and for several different volume sizes.
Ntfsclone validation on the bit level for both full and metadata image cloning.
Ntfsresize validation. The built-in NTFS consistency check of ntfsresize is regularly used during the test processes.
Ntfscmp validation.

Tests are done on newly created and aged volumes and partitions, moreover on forty aged, real-world, very diverse NTFS metadata images submitted from all over the world in the last four years.
Tests are done in the root, in newly created, empty and in old, non-empty directories.
NTFS consistency is checked after test runs.
Windows compatibility is checked after test runs.
Creation of 13,000 files in a directory and checking the directory consistency after every file creation.
Removal of 13,000 files from a directory and checking the directory consistency after every file removal.
Creation of 10 new files in each directory on real-world NTFS images and checking the directory consistency after every file creation.
Removal of maximum 10 files from each directory on real-world NTFS images and checking the directory consistency after every file removal.
Removal of all files on real-world NTFS images.
Rename test suite for POSIX and WIN32/DOS namespaces.
Renaming all files and directories on real-world NTFS images

to be lower case
to be upper case
to a different name

Bonnie++ is used for function and performance tests. Bonnie++ creates, checks and deletes 16,000 files per directory first sequentially, then randomly.
Fsx file system exerciser.
Creation, lookup, directory listing and removal of one million files in a single directory.
Fsfuzzer is used to create randomly corrupted NTFS volumes for detecting flaws, bugs, design problems in the file system parsing and handling code.
Permanent random file operations (create, delete, rename, etc) in full disk condition.
The following tests are executed and the identicality of the resulting directory trees is verified, along with their Windows compatibility.

rsync -a /mnt/ntfs1 /mnt/ntfs2
cp -r /usr /mnt/ntfs
cp -a /usr /mnt/ntfs

The following test suites are used:

Linux Test Project file system test cases.
IBM's jfstestcases.tar.gz package.
FUSE test suite.
Andrew Morton's ext3-tools.
POSIX file system test suite.

Randomly writing into a sparse file (ntfsclone).
Concurrently writing into several large files (tiotest).
Concurrently writing into a large file at several positions.
Writing huge files on highly fragmented volumes.
Testing swap file usage on NTFS, and Linux bootability from NTFS by LILO.
Ensuring file system consistency after unmounting and detaching removable devices during heavy file system activity.
General, every-day file system use where NTFS is the root file system.
The driver and the utilities are tested both with and without Valgrind.

These tests must pass flawlessly, or the known errors must be documented, in order to fulfill the quality criteria of a public driver release.

Testimonials

"ntfs-3g works INCREDIBLY well."

"NTFS support in linux is now excellent, thanks to the ntfs-3g project."

"I personally do not know what I'd do without it. It's very stable and very useful!"

"ntfs-3g is super easy to setup and works perfectly."

"Without ntfs-3g I would not use linux 99% of the time."

"APC Magazine has tested stability and speed of the new driver, NTFS-3g, and found it works flawlessly."

"ntfs-3g works much better and faster than captive-ntfs, so great work!"

"After all, there has been nothing wrong in ntfs-3g, but my hardware."

"SystemRescueCd allows mounting an NTFS partition with a full read/write support, and replaces CaptiveNtfs."

"ntfs-3g is VERY reliable and fast for reading and writing."

"I believe, ntfs-3g is superior to all other Linux ntfs drivers, including the commerical drivers. I highly recommend it."

"That [ntfs-3g] was the deal-breaker for me - without reliable NTFS read/write support, I would not have made the jump to Linux."

"ntfs-3g works just fine."

"From read/write reliability perspective, ntfs-3g is VERY good."

"ntfs-3g is a lot more stable on my system than Captive-NTFS was, and hasn't caused any trouble."

"It worked perfectly! ntfs-3g rocks!!"

"I've now been using this for a month and have had no problems at all."

"I highly recommend ntfs-3g, been even better than a commertial alternative I tried before."

"ntfs-3g works fine with my 32-bit system."

"I have been using it for a couple of months on a very regular basis and have not had any problems so far. Highly recommended !"

"Copied a huge directory tree with about 74 thousand files, total about 1+ GB. No problems."

"ntfs-3g works perfectly."

"I've installed it, and found strange how fast it is, even working with the fuse abstraction."

"Captive-NTFS was dropped in favour of NTFS-3G, which is faster, more reliable, and allows writing."

"ntfs-3g is working now and I won't fix something that's not broken."

"ntfs-3g works great."

"Since 2 weeks now, I'm using ntfs-3g with softwares which read/write a lot. Not any data corruption."

"ntfs-3g works fine for me."

"Using ntfs-3g here and all is working great. So much better than the in kernel support."

"Captive NTFS is miles behind NTFS-3G in both performance and stability."

"I've been using ntfs-3g with a great deal of success."

How To Test

No matter if you have Windows or not, or if you have NTFS partition or not, you're always able to test the NTFS driver using exclusively Linux, Mac OS X, FreeBSD or NetBSD. Here are the steps how it can be done.

Install ntfsprogs-1.13.1 for your operating system.
Prepare an NTFS volume for testing.

If you don't have an NTFS partition then create an NTFS file system either on an empty partition:

    mkntfs -f /dev/ntfs-test

or in a file:

    touch ntfs-test.img
    mkntfs -fF ntfs-test.img 1000000   # Create a 500 MB sparse NTFS image file.

If you have an NTFS partition then you can either clone the entire file system into a sparse image file:
```
    ntfsclone --overwrite ntfs-test.img /dev/ntfs-partition
```
or if you don't have enough space then clone only the NTFS metadata:
```
    ntfsclone --metadata --overwrite ntfs-test.img /dev/ntfs-partition
```

Mount the NTFS volume.

If you have a test NTFS partition then type:
```
    ntfs-3g /dev/ntfs-test /mnt/ntfs
```
or if you're using an NTFS image file then enter:
```
    ntfs-3g ntfs-test.img /mnt/ntfs
```