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Real-World Benchmarks of Ext4
Ashmash writes "Phoronix has put out a fresh series of benchmarks that show the real world performance of the Ext4 file-system. They ran 19 tests on Fedora 10 with changing out their primary partition to test Ext3, Ext4, Xfs, and ReiserFS. The Linux 2.6.27 kernel was used with the latest file-system support. In the disk benchmarks like Bonnie++ Ext4 was a clear winner but with the real world tests the results were much tighter and Xfs also possessed many wins. They conclude though that Ext4 is a nice upgrade over Ext3 due to the new features and just not improved performance in a few areas, but its lifespan may be short with btrfs coming soon."
and in the darkness... bind them.
Seriously... one of the nice things about Windows, OSX, Solaris is that they get a new filesystem once every 5-10 years. The safest thing to do for Linux is to be a generation behind. I would not run ext4 until btrfs came out. Why be the admin that gets screwed with early bugs and future incompatibilities...
It really depends on what the larger distros choose to stick with as their default. To be honest, I'd still be using ext2 if Redhat hadn't made ext3 the default. While I'm sure that some applications depend on wringing that last few % of performance out of the spindles, it just doesn't matter THAT much for most applications.
I wonder if ext4 performs better with SSD's? Or if ext4 doesn't need an occasional fsck like ext3 does?
--jeffk++
ipv6 is my vpn
it just doesn't matter THAT much for most applications
well... run an fsck against ext2 and ext3 and tell me it doesn't matter. For an admin, speed, reliability, recoverability... are all major concerns. On Solaris, I love ZFS because of the functionality like snapshots and exports. I also got burned by the IDE/100% CPU driver bug on Sparc hardware. Admins need to be aware of what they are running and what limitations exist. I honest don't give a damn about mp3 encoding speed, but the capabilities and maturity of a filesystem have to be considered.
I see no analysis as to why the filesystems perform the way they do. Why does XFS perform so well on a 4GB sequential read and so badly on an 8GB read? Why did they include cpu / gfx bound frame/sec benchmarks? In the few application benchmarks where there was more than a tiny fraction of percent difference there's no discussion as to whether that difference is actually significant.
Not at all enlightening.
Nick
Given that XFS, a 15+ year old file system, is still a serious contender, one would think enough blood has been squeezed from this stone. What is left to us is application tuning and hardware improvements, possibly including filesystem management hardware. It seems to me that teaching application developers how to write their programs to best utilize the filesystem is more likely to yield better performance gains for the effort expended than trying to make a general purpose filesystem good at any flavor of IO that application developers naively throw at it. Simple rules: buffer your IO yourself, perform raw accesses in multiples of the sector/stripe size size.
"If still these truths be held to be
Self evident."
-Edna St. Vincent Millay
What's with the CPU/Video tests? How about some more random access pattern tests, DB/web/streaming media tests? How about showing CPU utilization in addition to I/O performance?
Hey, ext4 actually speeds up fsck quite a lot, so maybe ext4 won't be around a lot of time ;)
Modded funny, but ext2 still has its uses. Journalling can be a bit of a performance breaker in the right (wrong) circumstances.
who measures things like MP3 compression time when testing a filesystem?!?
They were measuring what matters: "System performance" It very well could have been the case that the fastest file system, measured on a simple bench mark gives the worst MP3 compression time. Let's say the reason the filesystem is fast is because it uses a huge amount of CPU time and RAM. So a RAM based encrypted file system might be very fast, until you run an application on it.
It's a reasonable test and what it showed is that in the real-world performance is about the same
To be honest, I'd still be using ext2 if Redhat hadn't made ext3 the default.
Well thank goodness RedHat saved you from yourself, then!
It's not about performance, it's about journaling. Ext3 has it, ext2 doesn't, ergo by modern standards ext2 is crap. The only justification for using it was when the only journaling file systems for linux were unstable.
The enemies of Democracy are
Ha! B-Trees! And Linus Torvalds calls Macintosh HFS+ "retarded!" Soooooo funny! That's the newest and kewlest? Come on, HFS has been around since Macs had hard drives, and it used B-Trees! Seriously, nobody benchmarked ZFS, and that's where the real action is going to be headed. Lose two hard drives, your RAID is still AOK, and you can rebuild it on the fly!!! ZFS is the future.
Knowledge is power. Knowledge shared is power multiplied.
Yup, I use it for the /boot partition
You leave yours running 24/7 wasting electricity when you're not using it?
But I *do* use it 24/7, I don't have to be in front of it to use it (my screen does go off quite often).
XFS has been around for 15+ years and still makes a pretty good appearance on benchmarks. Which means that ext,ext2 and ext3 filesystems were late and have little to offer more, with ext4 just marginally (15 years to make something like ext4 with such minimally more performance?)
âoeFoolsâ to the Phoronix guys who thought that filesystems relate to in-game frames per second or compression. Most games preload all their stuff into RAM anyway. And compression is CPU-bound, your disk writes are done in the background anyway.
WTF who measures things like MP3 compression time when testing a filesystem?!?
Anyone interested in real world usage. Resource usage of the file system drivers while doing something processor intensive such as encoding is certainly of interest.
These posts express my own personal views, not those of my employer