In the last 10 years, Ext4 has risen in prominence, ReiserFS has fallen to the wayside, ZFS has been ported to Linux, XFS keeps plugging along, and there's a new kid: Btrfs. NTFS has evolved, too. It's now 2016. How do these filesystems stack up against each other? Does it really make that much of a difference? We’ll show you the results of standard, consistent tests across platforms (Linux vs. Windows) and filesystems to see if the differences are worth choosing one over the other. For simplicity's sake, the tests are performed on identical hardware with out-of-the-box settings.

1. Filesystem Showdown
What a difference a decade makes
Matt Janulewicz & Steve Oddo
Dolby Labs

2. 2
The Problem
 Perforce on Solaris is sunsetting
 Standardizing on Linux
• Which filesystem?
 Previous Merge presentations a decade old
 Perforce has recommendations, no numbers

3. 3
The Methodology
 Standard Perforce branch-submit benchmark
 Test on same physical hardware (retired master)
 Use out-of-the-box settings (aside from compression)
 Include Windows
 Software RAID drives (lvm, ZFS, BTRFS, Windows volume)
 Run tests five times, chart average

4. 4
The System
 Master server retired in March 2015
• 2 physical processors (Intel Xeon 2.2 Ghz)
• 16 cores (8 per CPU)
• 512 GB memory
 Ten SAS drives
• 3 TB each
• Samsung 7200 RPM 6 Gbps
 P4D 2015.1

5. 5
Filesystems and OS’s
 Solaris 11 x86_64
• ZFS (uncompressed/compressed lzjb)
 RedHat Linux 7.2
• ZFS (uncompressed/compressed lzjb)
• Ext3/Ext4
• Xfs
• BTRFS (uncompressed/compressed lzo/compressed zlib)
 Windows Server 2012R2
• NTFS/ReFS

6. 6
Datasets
 Branch-Submit
• ftp://ftp.perforce.com/perforce/tools/benchmarks/datasets/reference01.2
015.1.ckp.gz
 Miscellaneous Tests
• changes 6,478
• files 4,200,348
• revisions 5,658,595
• Integs 15,434,516
• total size 112 GB

7. 7
Results (Benchmark)
Winner: XFS
Honorable Mention:
BTRFS-compressed,
BTRFS-uncompressed,
ext3
Running Tally:
XFS: 1.0
BTRFS-c: 0.5
BTRFS-u: 0.5
ext3: 0.5

8. 8
Results (Benchmark)
Winner: BTRFS-c
Honorable Mention:
BTRFS-u, XFS, ext4, ext3
Running Tally:
XFS: 1.5
BTRFS-c: 1.5
BTRFS-u: 1.0
ext3: 1.0
ext4: 0.5

9. 9
Results (Benchmark)
Winner: BTRFS, ZFS-l
Honorable Mention:
XFS, ext4, ext3
Running Tally:
BTRFS-c: 2.5
XFS: 2.0
BTRFS-u: 2.0
ext3: 1.5
ext4: 1.0
ZFS-l: 1.0

10. 10
Results (Benchmark)
Winner: ZFS-l
Honorable Mention:
BTRFS-u, BTRFS-c
Running Tally:
BTRFS-c: 3.0
BTRFS-u: 2.5
XFS: 2.0
ZFS-l: 2.0
ext3: 1.5
ext4: 1.0

11. 11
Results (Benchmark)
Winner: XFS, ext4
Honorable Mention:
Ext3, BTRFS-c, BTRFS-u
Running Tally:
BTRFS-c: 3.5
XFS: 3.0
BTRFS-u: 3.0
ext4: 2.0
ZFS-l: 2.0
ext3: 1.5

12. 12
Results (Benchmark)
Winner: XFS, ext4
Honorable Mention:
Ext3, BTRFS-c, BTRFS-u
Running Tally:
XFS: 4.0
BTRFS-c: 4.0
BTRFS-u: 3.5
ext4: 3.0
ext3: 2.0
ZFS-l: 2.0

13. 13
Results (Miscellaneous)
Winner: ext3, BTRFS-u,
BTRFS-c, ext4, XFS
Honorable Mention:
Running Tally:
XFS: 5.0
BTRFS-c: 5.0
BTRFS-u: 4.5
ext4: 4.0
ext3: 3.0
ZFS-l: 2.0

14. 14
Results (Miscellaneous)
Winner: ext3, BTRFS-u,
BTRFS-c, ext4, XFS
Honorable Mention:
Running Tally:
XFS: 6.0
BTRFS-c: 6.0
BTRFS-u: 5.5
ext4: 5.0
ext3: 4.0
ZFS-l: 2.0

15. 15
Results (Miscellaneous)
Winner: BTRFS-c
Honorable Mention:
BTRFS-u, ext3
Running Tally:
BTRFS-c: 7.0
XFS: 6.0
BTRFS-u: 5.5
ext4: 5.0
ext3: 4.5
ZFS-l: 2.0

16. 16
Results (Miscellaneous)
Winner: BTRFS-u
Honorable Mention:
BTRFS-c, ext3, ZFS-l
Running Tally:
BTRFS-c: 7.5
BTRFS-u: 6.5
XFS: 6.0
ext3: 5.0
ext4: 5.0
ZFS-l: 2.5

17. 17
Results (Miscellaneous)
Winner: XFS, ext4
Honorable Mention:
BTRFS-c, BTRFS-u, ext3
Running Tally:
BTRFS-c: 8.0
XFS: 7.0
BTRFS-u: 7.0
ext3: 5.5
ext4: 5.0
ZFS-l: 2.5

18. Poor Performers:
Windows, ZFS
Better Performers:
Linux (anything)

19. 19
Final Thoughts
 Windows performs generally worse when compared to
almost any Linux filesystem.
 XFS is a solid choice. Supported, mature, fast.
 BTRFS compressed vs uncompressed not hugely different.
 Ext3 holds up surprisingly well. Go figure.

20. 20
Questions For You
 Are ZFS features worth the performance hit? (likely)
 Is BTRFS ready for primetime? (perhaps)
 Is Windows performance poor enough to justify introducing
Linux into your data center? (yes, yes it is)

21. Contact us for raw data
or further questions.
majanu@dolby.com
sjo@dolby.com