On Fri, 2008-04-04 at 20:19 +0900, Akira Fujita wrote: > Hi, > > Aneesh Kumar K.V wrote: > > you would need http://www.kernel.org/pub/software/devel/sparse/ > > to find and fix these warnings. > > I have updated ext4 online defrag to fix sparse warnings. > I also changed the construction of ext4 online defrag patches > to compile one-by-one and make them small but there is > no functional change since previous version. > Thanks, I have updated the patch queue with v8 > Outline for ext4 online defrag: > Ext4 online defrag has the following three functions. > > 1.[ no option ] Solving a single file fragmentation > Single file fragmentation is solved by moving file > data to contiguous free blocks. > > 2.[ -r ] Solving a relevant file fragmentation > Relevant file fragmentation could be solved by moving > the files under the specified directory close together with > the block containing the directory data. > > 3.[ -f ] Solving a free space fragmentation > If there is no contiguous free blocks in the filesystem, > the other files are moved to make sufficient space to allocate > contiguous blocks for the target file. > > Next steps: > 1. Rework of defrag functions based on review comments from Mingming. > 2. Implement defrag -f mode with FIEMAP ioctl. > 3. Remove the limit of target file size (now 128MB) in -f mode. > * Past mail concerning -f mode. > http://marc.info/?l=linux-ext4&m=118239067704899&w=4 > > Summary of patches: > * These patches are replaced with ext4 online defrag patches > which are already in the ext4 git tree (linux-2.6.26-rc8). > > [PATCH 1/8] Exchange the blocks between two inodes > - Exchange the data blocks between the temporary inode and > the original inode. > > [PATCH 2/8] Read and write file data with memory page > - Read the file data from the old blocks to the page and > write the file data on the page into the new blocks. > > [PATCH 3/8] Allocate new contiguous blocks with mballoc > - Search contiguous free blocks with mutil-block allocation > and allocate them for the temporary inode. > > [PATCH 4/8] Main function of ext4 online defrag and ioctl implementation > - Create the temporary inode and do defrag per > defrag_size (defalut 64MB). > I am curious about the ordering here. It seems reverse the order of the first 4 patches make the logic more clear to me, start from patch 4, then 3, then 2 and last 1? At lease when I read the describtion of the first patch I was puzzled by a minute what is this coming from Just share my thoughts. Mingming > [PATCH 5/8] Defragmentation for the relevant files (-r mode) > - Relevant file fragmentation could be solved by moving > the files under the specified directory close together with > the block containing the directory data. > > [PATCH 6/8] Check the free space fragmentation (-f mode) > - Check the free space fragmentation in the block group > where target file is located. > > [PATCH 7/8] Move victim files for the target file (-f mode) > - Move victim files to make sufficient space and reallocates > the contiguous blocks for the target file. > > [PATCH 8/8] Online defrag command > - The defrag command. Usage is as follows: > - Put the multiple files closer together. > # e4defrag -r directory-name > - Defrag for free space fragmentation. > # e4defrag -f file-name > - Defrag for a single file. > # e4defrag file-name > - Defrag for all files on ext4. > # e4defrag device-name > > Comments and reviews are welcome. > > Regards, > Akira > -- > 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
