On Thu, 24 Dec 2009 at 16:27, ty...@mit.edu wrote: > If you don't do a "sync" after the tar, then in most cases you will be > measuring the memory bandwidth, because data won't have been written
Well, I do "sync" after each operation, so the data should be on disk, but that doesn't mean it'll clear the filesystem buffers - but this doesn't happen that often in the real world too. Also, all filesystem were tested equally (I hope), yet some filesystem perform better than another - even if all the content copied/tar'ed/removed would perfectly well fit into the machines RAM. > Another good example of well done file system benchmarks can be found > at http://btrfs.boxacle.net Thanks, I'll have a look at it and perhaps even integrate it in the wrapper script. > benchmarks for a living. Note that JFS and XFS come off much better > on a number of the tests Indeed, I was surpised to see JFS perform that good and XFS of course is one of the best too - I just wanted to point out that both of them are strangely slow at times (removing or creating many files) - not what I expected. > --- and that there is a *large* number amount > of variation when you look at different simulated workloads and with a > varying number of threads writing to the file system at the same time. True, the TODO list in the script ("different benchmark options") is in there for a reason :-) Christian. -- BOFH excuse #291: Due to the CDA, we no longer have a root account. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
