On 02/22/2012 07:44 AM, Andreas Dilger wrote: > On 2012-02-20, at 12:00 AM, Tao Ma wrote: >> Hi Ted, Andreas and list, >> This is the v4 attempt to add inline data support to ext4 inode. >> For more information about the background, please refer to the thread >> http://marc.info/?l=linux-ext4&m=131715205428067&w=2 >> >> Changlog from v3 to v4: >> 1. Add support for truncate which is really a bug. >> 2. Some bug fixes. >> 3. rebased to the latest kernel. > > I'm starting to look through this patch series, and a number of things are Thanks for the review. > missing that would make it much easier to understand and accept: > - a good comment and possibly a diagram at the start of fs/ext4/xattr.c > that describes where and how the inline data is stored in the inode, > what the policies are for storing data inline or externally, etc. sure, I will add it. > - some benchmark data that shows why landing this code is desirable. > My comments in the above thread show that small files and directories > could benefit from this, but real proof now that you have made this > patch is whether this translates into noticeable space savings, and > hopefully also noticeable performance improvements in some benchmarks: > - I suspect that running some tests with bigalloc + 512-byte inodes > or similar could show significant space savings and speedups for > cold-cache directory traversal > - measuring boot time on a distro with Gnome or KDE could show real > speedups due to the many small files and directories used at startup > - running a benchmark like mongo or postmark with small files and > with 256- or 512-byte inodes may also show real speedups > - is there some workload that you are using that shows speedups that > could be described in general terms and show relative performance, > even if it is not possible to supply the actual benchmark/tests? OK, I was just playing around with some bug fixes these days(to make it stable in our production system) and doesn't do some performance tests when upgrading from v2 to v3. I will try to do some tests and return the data back in v5. Thanks Tao > > I'll go through the patches and suggest cleanups and improvements, but > without improved documentation and real performance tests the patch is > very unlikely to be accepted by Ted. > >> Changelog from v2 to v3: >> 1. Add support for evict data from inode if we can store xattr in it. >> 2. Add support for fiemap >> 3. Some nasty bug fixes >> >> The v3 can be found here: >> http://marc.info/?l=linux-ext4&m=132421821001634&w=2 >> >> The v2 can be found here: >> http://marc.info/?l=linux-ext4&m=132189338604177&w=2 >> >> The v1 can be found here: >> http://marc.info/?l=linux-ext4&m=131961438221255&w=2 >> >> any suggestions are welcomed. >> >> Thanks >> Tao > > > Cheers, Andreas > > > > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
