git-am is a commonly used command for applying a series of patches from a mailbox to the current branch. Currently, it is implemented by the shell script git-am.sh. However, compared to C, shell scripts have certain deficiencies: they need to spawn a lot of processes, introduce a lot of dependencies and cannot take advantage of git's internal caches. This WIP patch series rewrites git-am.sh into optimized C builtin/am.c. It is based on my finished prototype of the rewrite[1], and over the next 5 weeks I will be cutting out small patches from the prototype to make it easier to review and refine the patch series. This is part of my GSoC project to rewrite git-pull.sh into git-am.sh into C builtins[2]. A small benchmark that applies 50 patches[3]: #!/bin/sh git init && echo initial >file && git add file && git commit -m initial && git branch before-am && for x in $(seq 50) do echo $x >>file && git commit -a -m $x done && git format-patch --stdout before-am.. >patches && git checkout before-am && time git patches >/dev/null I ran this benchmark on my *Linux* system. Timings for git on master: 1.40s, 1.42s, 1.25s, 1.32s, 1.10s. Avg: ~1.30s Timings for git on master + this patch series applied: 0.24s, 0.22s, 0.22s, 0.19s, 0.25s. Avg: ~0.22s This is around a 6x speedup. It's not because this patch series does less than git-am.sh -- similar speedups can be observed with the prototype, which passes the test suite[4]. (Sorry for leaving the other reviews hanging. I was too preoccupied with the git-am rewrite, and was afraid of forgetting important details should I context switch. Now that the prototype is finished I can deal with the other patch series'.) [1] https://github.com/pyokagan/git/compare/master...pyokagan:pt/ref-builtin-am [2] https://gist.github.com/pyokagan/1b7b0d1f4dab6ba3cef1 [3] Since a 56-patch series was posted recently ;-) [4] The subset of the test suite that calls git-rebase and git-am. Paul Tan (8): wrapper: implement xopen() wrapper: implement xfopen() am: implement patch queue mechanism am: split out mbox/maildir patches with git-mailsplit am: detect mbox patches am: extract patch, message and authorship with git-mailinfo am: apply patch with git-apply am: commit applied patch Makefile | 2 +- builtin.h | 1 + builtin/am.c | 687 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ git-compat-util.h | 2 + git.c | 1 + wrapper.c | 37 +++ 6 files changed, 729 insertions(+), 1 deletion(-) create mode 100644 builtin/am.c -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html