[PATCH v1 00/10] cat-file speedups

This continues the work of Jeff King and my initial work to speed up cat-file --batch(-contents)? users in https://lore.kernel.org/git/20240621062915.GA2105230@coredump.intra.peff.net/T/

There's more speedups I'm working on, but this series touches on the work Jeff and I have already published.

I've started putting some Perl5 + Inline::C benchmarks with several knobs up at: git clone https://80x24.org/misc-git-benchmarks.git

I've found it necessary to use schedtool(1) on Linux to pin all processes to a single CPU on multicore systems.

Some patches make more sense for largish objects, some for smaller objects. Small objects (several KB) were my main focus, but I figure 5/10 could help with some pathological big cases and also open the door to expanding the use of caching down the line.

10/10 actually ended up being more significant than I originally anticipated for repeat lookups of the same objects (common for web frontends getting hammered).

Jeff: I started writing commit messages for your patches (1 and
2), but there's probably better explanations you could do :>

Eric Wong (8):
  packfile: fix off-by-one in content_limit comparison
  packfile: inline cache_or_unpack_entry
  cat-file: use delta_base_cache entries directly
  packfile: packed_object_info avoids packed_to_object_type
  object_info: content_limit only applies to blobs
  cat-file: batch-command uses content_limit
  cat-file: batch_write: use size_t for length
  cat-file: use writev(2) if available

Jeff King (2):
  packfile: move sizep computation
  packfile: allow content-limit for cat-file

 Makefile            |   3 ++
 builtin/cat-file.c  | 124 +++++++++++++++++++++++++++++++-------------
 config.mak.uname    |   5 ++
 git-compat-util.h   |  10 ++++
 object-file.c       |  12 +++++
 object-store-ll.h   |   8 +++
 packfile.c          | 120 ++++++++++++++++++++++++++----------------
 packfile.h          |   4 ++
 t/t1006-cat-file.sh |  19 +++++--
 wrapper.c           |  18 +++++++
 wrapper.h           |   1 +
 write-or-die.c      |  66 +++++++++++++++++++++++
 write-or-die.h      |   2 +
 13 files changed, 308 insertions(+), 84 deletions(-)