On Tue, Jul 05, 2016 at 08:52:26AM +1000, Dave Chinner wrote: > [xfs@xxxxxxxxxxx is where you'll find the XFS developers] > > On Mon, Jul 04, 2016 at 05:32:40AM +0000, Wang Shilong wrote: > > Hello Guys, > > > > I happened run some benchmarks for XFS, and found some intresting to share here: > > Kernel version: > > [root@localhost shm]# uname -r > > 4.7.0-rc5+ > > > > [root@localhost shm]# cat /proc/cpuinfo | grep Intel > > vendor_id : GenuineIntel > > model name : Intel(R) Core(TM) i7-4770 CPU @ 3.40GHz What's the rest of the hardware in the machine? > > dd 16GB to /dev/shm/data to use memory backend storage to benchmark metadata performaces. I've never seen anyone create a ramdisk like that before. What's the backing device type? i.e. what block device driver does this use? > > Benchmark tool is mdtest, you can download it from > > https://sourceforge.net/projects/mdtest/ What version? The sourceforge version, of the github fork that the sourceforge page points to? Or the forked branch of recent development in the github fork? > > Steps to run benchmark > > #mkfs.xfs /dev/shm/data Output of this command so we can recreate the same filesystem structure? > > #mount /dev/shm/data /mnt/test > > #mdtest -d /mnt/test -n 2000000 > > > > 1 tasks, 2000000 files/directories > > > > SUMMARY: (of 1 iterations) > > Operation Max Min Mean Std Dev > > --------- --- --- ---- ------- > > Directory creation: 24724.717 24724.717 24724.717 0.000 > > Directory stat : 1156009.290 1156009.290 1156009.290 0.000 > > Directory removal : 103496.353 103496.353 103496.353 0.000 > > File creation : 23094.444 23094.444 23094.444 0.000 > > File stat : 1158704.969 1158704.969 1158704.969 0.000 > > File read : 752731.595 752731.595 752731.595 0.000 > > File removal : 105481.766 105481.766 105481.766 0.000 > > Tree creation : 2229.827 2229.827 2229.827 0.000 > > Tree removal : 1.275 1.275 1.275 0.000 > > > > -- finished at 07/04/2016 12:54:26 -- A table of numbers with no units or explanation as to what they mean. Let me guess - I have to read the benchmark source code to understand what the numbers mean? > > IOPS for file creation is only 2.3W, however compare to Ext4 with same testing. Ummm - what unit of measurement is "W"? Watts? Please, when presenting benchmark results to ask for help with analysis, be *extremely specific* about what you running and what the results mean. It's no different from reporting a bug from this perspective: http://xfs.org/index.php/XFS_FAQ#Q:_What_information_should_I_include_when_reporting_a_problem.3F That said, this is a single threaded benchmark. It's well known that XFS uses more CPU per metadata operation than either ext4 or btrfs, so it won't be any surprise that they are faster than XFS on this particular test. We've known this for many years now - perhaps you should watch/read this presentation I did more than 4 years ago now: http://xfs.org/index.php/File:Xfs-scalability-lca2012.pdf http://www.youtube.com/watch?v=FegjLbCnoBw IOWs: Being CPU bound at 25,000 file creates/s is in line with what I'd expect on XFS for a single threaded, single directory create over 2 million directory entries with the default 4k directory block size.... Cheers, Dave. -- Dave Chinner david@xxxxxxxxxxxxx _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
