[PATCH v4 0/9] Reduce index load time

This is the rebased version since last time [1] with s/free_index_shm/release_index_shm/ as suggested by David Turner. It introduces a daemon that can cache index data in memory so that subsequent git processes can avoid reading (and more importantly, verifying) the index from disk. Together with split-index it should keep index I/O cost down to minimum. The series can also be found at [2].

One of the factors that affected my design was Windows support. We now have Dscho back, he can evaluate my approach for Windows.

This daemon is the foundation for watchman support later to reduce refresh time. To be posted shortly after this.

[0] http://mid.gmane.org/1406548995-28549-1-git-send-email-pclouds@gmail.com [2] http://github.com/pclouds/git/commits/index-helper

Nguyễn Thái Ngọc Duy (9):
  trace.c: add GIT_TRACE_PACK_STATS for pack usage statistics
  read-cache.c: fix constness of verify_hdr()
  read-cache: allow to keep mmap'd memory after reading
  index-helper: new daemon for caching index and related stuff
  trace.c: add GIT_TRACE_INDEX_STATS for index  statistics
  index-helper: add --strict
  daemonize(): set a flag before exiting the main process
  index-helper: add --detach
  index-helper: add Windows support

 .gitignore                               |   1 +
 Documentation/git-index-helper.txt (new) |  56 +++++++
 Documentation/git.txt                    |   4 +
 Makefile                                 |   9 ++
 builtin/gc.c                             |   2 +-
 cache.h                                  |  12 +-
 config.mak.uname                         |   3 +
 daemon.c                                 |   2 +-
 git-compat-util.h                        |   1 +
 git.c                                    |   1 +
 index-helper.c (new)                     | 264 +++++++++++++++++++++++++++++++
 read-cache.c                             | 147 ++++++++++++++++-
 setup.c                                  |   4 +-
 sha1_file.c                              |  24 +++
 shm.c (new)                              | 163 +++++++++++++++++++
 shm.h (new)                              |  23 +++
 trace.c                                  |  16 ++
 trace.h                                  |   1 +
 18 files changed, 721 insertions(+), 12 deletions(-)
 create mode 100644 Documentation/git-index-helper.txt
 create mode 100644 index-helper.c
 create mode 100644 shm.c
 create mode 100644 shm.h