[RFC PATCH 0/5] Put struct inode on a diet

[Theodore Ts'o <tytso@mit.edu>]

These patches attempt to slim down struct inode to reduce the overhead
of storing cached inodes.  A typical Linux system has hundreds of
thousands of inodes cached, if not more, so reducing the inode size is a
high leverage thing to do.  For example these patches save 24 bytes, or
a little over 4% of an inode (with no debugging enabled) on an x86_64
machine.  But on a system with 160,000 inodes in its inode cache, this
might mean a difference of six and half megabytes of physical memory
(once SLAB rounding issues are taken into account).

Theodore Ts'o (5):
  fs: i_flags and i_state in struct inode only need to be unsigned
    short
  fs: Remove i_cindex from struct inode
  fs: Slim down inode by only using an unsigned int for i_dnotify_mask
  fs: Rearrange inode structure elements to avoid waste due to padding
  Dump the inode structure (for debugging purposes only)

 drivers/ieee1394/dv1394.c        |    5 +-
 drivers/ieee1394/ieee1394_core.h |    5 ++-
 fs/Makefile                      |    1 +
 fs/char_dev.c                    |   14 ++++++-
 fs/inode-struct-dumper.c         |   87 ++++++++++++++++++++++++++++++++++++++
 include/linux/cdev.h             |    2 +
 include/linux/dnotify.h          |    2 +-
 include/linux/fs.h               |    9 ++--
 8 files changed, 115 insertions(+), 10 deletions(-)
 create mode 100644 fs/inode-struct-dumper.c