From: Zhi Yong Wu <wuzhy@xxxxxxxxxxxxxxxxxx> The patchset is trying to introduce hot tracking function in VFS layer, which will keep track of real disk I/O in memory. By it, you will easily know more details about disk I/O, and then detect where disk I/O hot spots are. Also, specific FS can take use of it to do accurate defragment, and hot relocation support, etc. Now it's time to send out its V4 for external review, and any comments or ideas are appreciated, thanks. NOTE: The patchset can be obtained via my kernel dev git on github: git://github.com/wuzhy/kernel.git hot_tracking If you're interested, you can also review them via https://github.com/wuzhy/kernel/commits/hot_tracking For how to use and more other info and performance report, please check hot_tracking.txt in Documentation and following links: 1.) http://lwn.net/Articles/525651/ 2.) https://lkml.org/lkml/2012/12/20/199 Changelog from v3: - Removed debugfs support, but leave it to TODO list [viro, Chandra] - Killed HOT_DELETING and HOT_IN_LIST flag [viro] - Fixed unlink issues [viro] - Fixed the issue on lookups (both for inode and range) leak on race with unlink [viro] - Killed hot_comm_item and split the functions which take it [virio] - Fixed some other issues [zwu, Chandra] v3: - Added memory caping function for hot items [Zhiyong] - Cleanup aging function [Zhiyong] v2: - Refactored to be under RCU [Chandra Seetharaman] Merged some code changes [Chandra Seetharaman] - Fixed some issues [Chandra Seetharaman] v1: - Solved 64 bits inode number issue. [David Sterba] - Embed struct hot_type in struct file_system_type [Darrick J. Wong] - Cleanup Some issues [David Sterba] - Use a static hot debugfs root [Greg KH] rfcv4: - Introduce hot func registering framework [Zhiyong] - Remove global variable for hot tracking [Zhiyong] - Add btrfs hot tracking support [Zhiyong] rfcv3: 1.) Rewritten debugfs support based seq_file operation. [Dave Chinner] 2.) Refactored workqueue support. [Dave Chinner] 3.) Turn some Micro into be tunable [Zhiyong, Liu Zheng] TIME_TO_KICK, and HEAT_UPDATE_DELAY 4.) Cleanedup a lot of other issues [Dave Chinner] rfcv2: 1.) Converted to Radix trees, not RB-tree [Zhiyong, Dave Chinner] 2.) Added memory shrinker [Dave Chinner] 3.) Converted to one workqueue to update map info periodically [Dave Chinner] 4.) Cleanedup a lot of other issues [Dave Chinner] rfcv1: 1.) Reduce new files and put all in fs/hot_tracking.[ch] [Dave Chinner] 2.) The first three patches can probably just be flattened into one. [Marco Stornelli , Dave Chinner] Dave Chinner (1): VFS hot tracking, xfs: Add hot tracking support Zhi Yong Wu (9): VFS hot tracking: Define basic data structures and functions VFS hot tracking: Track IO and record heat information VFS hot tracking: Add a workqueue to move items between hot maps VFS hot tracking: Add shrinker functionality to curtail memory usage VFS hot tracking: Add an ioctl to get hot tracking information VFS hot tracking: Add a /proc interface to make the interval tunable VFS hot tracking: Add a /proc interfaces to control memory usage VFS hot tracking: Add documentation VFS hot tracking, btrfs: Add hot tracking support Documentation/filesystems/00-INDEX | 2 + Documentation/filesystems/hot_tracking.txt | 207 +++++++ fs/Makefile | 2 +- fs/btrfs/ctree.h | 1 + fs/btrfs/super.c | 22 +- fs/compat_ioctl.c | 5 + fs/dcache.c | 2 + fs/direct-io.c | 5 + fs/hot_tracking.c | 833 +++++++++++++++++++++++++++++ fs/hot_tracking.h | 66 +++ fs/ioctl.c | 68 +++ fs/namei.c | 3 + fs/xfs/xfs_mount.h | 1 + fs/xfs/xfs_super.c | 18 + include/linux/fs.h | 4 + include/linux/hot_tracking.h | 148 +++++ kernel/sysctl.c | 14 + mm/filemap.c | 6 + mm/page-writeback.c | 12 + mm/readahead.c | 6 + 20 files changed, 1423 insertions(+), 2 deletions(-) create mode 100644 Documentation/filesystems/hot_tracking.txt create mode 100644 fs/hot_tracking.c create mode 100644 fs/hot_tracking.h create mode 100644 include/linux/hot_tracking.h -- 1.7.11.7 -- 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