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Linux File System Shootout
IpSo_ writes "Finally an extensive, human readable Linux file system benchmark has been unleashed upon us. Originally posted on the Linux Kernel mailing list, using two of the most popular benchmarking tools available, it compares all the major file systems, including their different mount options. The results are surprising."
There is have focus on throughput in these benchmarks. Reading and writing lots of data, seeking in files and reading data, etc.
Notably missing are more day-to-day useful operations such as the creation and deletion of lots of files, parallel action on many open files,
lots of files in a directory, etc.
When I want to select a filesystem, I do not want to know how fast it can read a 3GB file sequentially. I want to know how well it performs on a fileserver, mailserver etc.
The human readable result is you need to know what you want. There is no silver bullet.
It looks like xfs wipes the floor for all but temporary (loads of create/delete) file usage. Jfs looks like the best all-rounder. Reiser looks like something that can be tuned to the specific usage, but eats CPU for breakfast, lunch and dinner and EXT3 "surprise, surprise" sucks rocks. The other "surprise, surprise" is that EXT2 is still very good for many uses.
Frankly, I do not see anything new and fascinating in the results, but they are good to throw at people who keep asking me "why not EXT3" and "Why XFS or EXT2". Here is why!
Baker's Law: Misery no longer loves company. Nowadays it insists on it
http://www.sigsegv.cx/
I'm not trying to be an asshole or a troll; just hear me out.
I love Reiser. I also love Gentoo and adore Debian. Myself and another guy, Joe, are the main "linux geeks" in our computer group (cugy.net). When it came time to decide what to support at our group, we had to choose RedHat.
If I'm in a message board or IRC channel, I need to know some things about the guy I'm helping. We reccomend RedHat because that is the biggest US company behind Linux (IBM and SUN notwithstanding). If I am teaching people about Linux, then it is to both our advantages to teach/learn about what we will see "in the field". Therefore, we only support RedHat.
What does this have to do with anything? Well, RedHat 9 and Severn do not allow the creation of Reiser by default. I could probably boot from a Gentoo disk and format a partition to Reiser, then install RedHat to it. But, by default, only ext* is allowed.
I love to do things that improve performance. I love testing new things on my laptop or on a offline box in our test lab. But unless RedHat offers it, it will remain in the shadows of the linux world, which is, in turn, in the shadows of the user enclave. Hell, of every important box on my network, they are either RedHat or Win2k.
More on topic, Joe got a lot of recognition when the "internet got a lot faster". Did he upgrade the firewall? Did he install another OC-3? Maybe he reconfigured services on the proxy?
Nope, he installed a hard drive, formatted it to Reiser, and moved the proxy cache to the reiser disk. I couldn't belive it. Just changing the filesystem caused an increase that was noticable across our network. At no cost!
Good work, Joe.
I'd rather you do it wrong, than for me to have to do it at all.
worst: reiser4/reiser4_extents
You might think that just based on the amount of red in Reiser4's row, but if you look all the way over to the right, you'll notice something interesting: Reiser4 often completes the benchmark in significantly less time than the other filesystems. Reiser seems to be caching a lot of flak for the CPU usage (certainly it gets a lot of red boxes in this benchmark because of it). Personally, though, I've got CPU to spare. Disk seek times aren't changing drastically anytime soon, unlike CPU speeds. If I can trade some CPU cycles for less wasted disk seek time, I think that's a great trade.
main(c,r){for(r=32;r;) printf(++c>31?c=!r--,"\n":c<r?" ":~c&r?" `":" #");}
Filesystem benchmarks can be remarkably inconsistent. These tables do not display average difference between runs. Usually this means that the methodology used to do the benchmarking is lax, and thus, untrustworthy.
For example, consider that harddrives do their own error correction. Depending on the location of marginal blocks on the media, different file systems can score dramatically for no other reason than the drive's re-mapping or error correction logic is kicking in at a bad point. Alignment of data can also be a factor in performace which depending on the formatting procedure may be completely random when compared to the file system sitting on top of it.
For these reasons and a host of others, it is not reliable to do filesystem performance comparison on a single machine.
Bottom line is that there is a good chance that these data are not fair representations of the relative merits of each filesystem.