From: John Cai <johncai86@xxxxxxxxx> When format is passed into --batch, --batch-check, --batch-command, the format gets expanded. When nothing is passed in, the default format is set and the expand_format() gets called. We can save on these cycles by hardcoding how to print the information when nothing is passed as the format, or when the default format is passed. There is no need for the fully expanded format with the default. Since batch_object_write() happens on every object provided in batch mode, we get a nice performance improvement. git rev-list --all > /tmp/all-obj.txt git cat-file --batch-check </tmp/all-obj.txt with HEAD^: Time (mean ± σ): 57.6 ms ± 1.7 ms [User: 51.5 ms, System: 6.2 ms] Range (min … max): 54.6 ms … 64.7 ms 50 runs with HEAD: Time (mean ± σ): 49.8 ms ± 1.7 ms [User: 42.6 ms, System: 7.3 ms] Range (min … max): 46.9 ms … 55.9 ms 56 runs If nothing is provided as a format argument, or if the default format is passed, skip expanding of the format and print the object info with a default format. See https://lore.kernel.org/git/87eecf8ork.fsf@xxxxxxxxxxxxxxxxxxx/ Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@xxxxxxxxx> Signed-off-by: John Cai <johncai86@xxxxxxxxx> --- optimize cat file batch info writing When cat-file --batch or --batch-check is used, we can skip having to expand the format if no format is specified or if the default format is specified. In this case we know exactly how to print the objects without the full expanded format. This was first discussed in [1]. We get a little performance boost from this optimization because this happens for each objects provided to --batch, --batch-check, or --batch-command. Because batch_object_write() is called on every oid provided in batch mode, this optimization adds up when a large number of oid info is printed. git rev-list --all >/tmp/all-objs.txt git cat-file --batch-check </tmp/all-obj.txt (with hyperfine) run on origin/master: Time (mean ± σ): 57.6 ms ± 1.7 ms [User: 51.5 ms, System: 6.2 ms] Range (min … max): 54.6 ms … 64.7 ms 50 runs run on jc/optimize-cat-file-batch-default-format: Time (mean ± σ): 49.8 ms ± 1.7 ms [User: 42.6 ms, System: 7.3 ms] Range (min … max): 46.9 ms … 55.9 ms 56 runs Changes since v1: * set opt->format in batch_objects so that the loop that prints objects only has to check if the format is null to know to print the object info in the default format * fixed up commit trailer to include Ævar as Signed-off-by 1. https://lore.kernel.org/git/87eecf8ork.fsf@xxxxxxxxxxxxxxxxxxx/ Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-git-1221%2Fjohn-cai%2Fjc%2Foptimize-cat-file-batch-default-format-v2 Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-git-1221/john-cai/jc/optimize-cat-file-batch-default-format-v2 Pull-Request: https://github.com/git/git/pull/1221 Range-diff vs v1: 1: 9f659b36c8f ! 1: f5d578d14a9 cat-file: skip expanding default format @@ Commit message passed, skip expanding of the format and print the object info with a default format. - Based-on-patch-by: Ævar Arnfjörð Bjarmason <avarab@xxxxxxxxx> - Signed-off-by: John Cai <johncai86@xxxxxxxxx> - See https://lore.kernel.org/git/87eecf8ork.fsf@xxxxxxxxxxxxxxxxxxx/ + Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@xxxxxxxxx> + Signed-off-by: John Cai <johncai86@xxxxxxxxx> + ## builtin/cat-file.c ## -@@ - #include "object-store.h" - #include "promisor-remote.h" - -+static const char *default_format = "%(objectname) %(objecttype) %(objectsize)"; - struct batch_options { - int enabled; - int follow_symlinks; @@ builtin/cat-file.c: static void print_object_or_die(struct batch_options *opt, struct expand_data *d } } -+static void print_default_format(char *buf, int len, struct expand_data *data) ++static int print_default_format(char *buf, int len, struct expand_data *data) +{ -+ snprintf(buf, len, "%s %s %"PRIuMAX"\n", oid_to_hex(&data->oid), ++ return xsnprintf(buf, len, "%s %s %"PRIuMAX"\n", oid_to_hex(&data->oid), + data->info.type_name->buf, + (uintmax_t)*data->info.sizep); + @@ builtin/cat-file.c: static void batch_object_write(const char *obj_name, struct packed_git *pack, off_t offset) { -+ const char *fmt; -+ + struct strbuf type_name = STRBUF_INIT; ++ + if (!opt->format) + data->info.type_name = &type_name; + @@ builtin/cat-file.c: static void batch_object_write(const char *obj_name, } } -+ if (!opt->format && !opt->print_contents) { +- strbuf_reset(scratch); +- strbuf_expand(scratch, opt->format, expand_format, data); +- strbuf_addch(scratch, '\n'); +- batch_write(opt, scratch->buf, scratch->len); ++ if (!opt->format) { + char buf[1024]; -+ -+ print_default_format(buf, 1024, data); -+ batch_write(opt, buf, strlen(buf)); -+ goto cleanup; ++ int len = print_default_format(buf, 1024, data); ++ batch_write(opt, buf, len); ++ } else { ++ strbuf_reset(scratch); ++ strbuf_expand(scratch, opt->format, expand_format, data); ++ strbuf_addch(scratch, '\n'); ++ batch_write(opt, scratch->buf, scratch->len); + } -+ -+ fmt = opt->format ? opt->format : default_format; - strbuf_reset(scratch); -- strbuf_expand(scratch, opt->format, expand_format, data); -+ strbuf_expand(scratch, fmt, expand_format, data); - strbuf_addch(scratch, '\n'); - batch_write(opt, scratch->buf, scratch->len); -@@ builtin/cat-file.c: static void batch_object_write(const char *obj_name, + if (opt->print_contents) { print_object_or_die(opt, data); batch_write(opt, "\n", 1); } @@ builtin/cat-file.c: static void batch_object_write(const char *obj_name, static void batch_one_object(const char *obj_name, struct strbuf *scratch, struct batch_options *opt, +@@ builtin/cat-file.c: static int batch_unordered_packed(const struct object_id *oid, + data); + } + ++ ++#define DEFAULT_FORMAT "%(objectname) %(objecttype) %(objectsize)" ++ + static int batch_objects(struct batch_options *opt) + { + struct strbuf input = STRBUF_INIT; @@ builtin/cat-file.c: static int batch_objects(struct batch_options *opt) - struct expand_data data; int save_warning; int retval = 0; -- + - if (!opt->format) - opt->format = "%(objectname) %(objecttype) %(objectsize)"; -+ const char *fmt; - +- /* * Expand once with our special mark_query flag, which will prime the + * object_info to be handed to oid_object_info_extended for each @@ builtin/cat-file.c: static int batch_objects(struct batch_options *opt) */ memset(&data, 0, sizeof(data)); data.mark_query = 1; - strbuf_expand(&output, opt->format, expand_format, &data); -+ fmt = opt->format ? opt->format : default_format; -+ strbuf_expand(&output, fmt, expand_format, &data); ++ strbuf_expand(&output, ++ opt->format ? opt->format : DEFAULT_FORMAT, ++ expand_format, ++ &data); data.mark_query = 0; strbuf_release(&output); if (opt->cmdmode) + data.split_on_whitespace = 1; + ++ if (opt->format && !strcmp(opt->format, DEFAULT_FORMAT)) ++ opt->format = NULL; + /* + * If we are printing out the object, then always fill in the type, + * since we will want to decide whether or not to stream. ## t/perf/p1006-cat-file.sh (new) ## @@ builtin/cat-file.c | 46 ++++++++++++++++++++++++++++++++-------- t/perf/p1006-cat-file.sh | 16 ++++++++++++++ 2 files changed, 53 insertions(+), 9 deletions(-) create mode 100755 t/perf/p1006-cat-file.sh diff --git a/builtin/cat-file.c b/builtin/cat-file.c index 7b3f42950ec..ab9a49e13a4 100644 --- a/builtin/cat-file.c +++ b/builtin/cat-file.c @@ -351,6 +351,14 @@ static void print_object_or_die(struct batch_options *opt, struct expand_data *d } } +static int print_default_format(char *buf, int len, struct expand_data *data) +{ + return xsnprintf(buf, len, "%s %s %"PRIuMAX"\n", oid_to_hex(&data->oid), + data->info.type_name->buf, + (uintmax_t)*data->info.sizep); + +} + /* * If "pack" is non-NULL, then "offset" is the byte offset within the pack from * which the object may be accessed (though note that we may also rely on @@ -363,6 +371,11 @@ static void batch_object_write(const char *obj_name, struct packed_git *pack, off_t offset) { + struct strbuf type_name = STRBUF_INIT; + + if (!opt->format) + data->info.type_name = &type_name; + if (!data->skip_object_info) { int ret; @@ -377,21 +390,31 @@ static void batch_object_write(const char *obj_name, printf("%s missing\n", obj_name ? obj_name : oid_to_hex(&data->oid)); fflush(stdout); - return; + goto cleanup; } } - strbuf_reset(scratch); - strbuf_expand(scratch, opt->format, expand_format, data); - strbuf_addch(scratch, '\n'); - batch_write(opt, scratch->buf, scratch->len); + if (!opt->format) { + char buf[1024]; + int len = print_default_format(buf, 1024, data); + batch_write(opt, buf, len); + } else { + strbuf_reset(scratch); + strbuf_expand(scratch, opt->format, expand_format, data); + strbuf_addch(scratch, '\n'); + batch_write(opt, scratch->buf, scratch->len); + } if (opt->print_contents) { print_object_or_die(opt, data); batch_write(opt, "\n", 1); } + +cleanup: + strbuf_release(&type_name); } + static void batch_one_object(const char *obj_name, struct strbuf *scratch, struct batch_options *opt, @@ -508,6 +531,9 @@ static int batch_unordered_packed(const struct object_id *oid, data); } + +#define DEFAULT_FORMAT "%(objectname) %(objecttype) %(objectsize)" + static int batch_objects(struct batch_options *opt) { struct strbuf input = STRBUF_INIT; @@ -516,9 +542,6 @@ static int batch_objects(struct batch_options *opt) int save_warning; int retval = 0; - if (!opt->format) - opt->format = "%(objectname) %(objecttype) %(objectsize)"; - /* * Expand once with our special mark_query flag, which will prime the * object_info to be handed to oid_object_info_extended for each @@ -526,12 +549,17 @@ static int batch_objects(struct batch_options *opt) */ memset(&data, 0, sizeof(data)); data.mark_query = 1; - strbuf_expand(&output, opt->format, expand_format, &data); + strbuf_expand(&output, + opt->format ? opt->format : DEFAULT_FORMAT, + expand_format, + &data); data.mark_query = 0; strbuf_release(&output); if (opt->cmdmode) data.split_on_whitespace = 1; + if (opt->format && !strcmp(opt->format, DEFAULT_FORMAT)) + opt->format = NULL; /* * If we are printing out the object, then always fill in the type, * since we will want to decide whether or not to stream. diff --git a/t/perf/p1006-cat-file.sh b/t/perf/p1006-cat-file.sh new file mode 100755 index 00000000000..e463623f5a3 --- /dev/null +++ b/t/perf/p1006-cat-file.sh @@ -0,0 +1,16 @@ +#!/bin/sh + +test_description='Basic sort performance tests' +. ./perf-lib.sh + +test_perf_large_repo + +test_expect_success 'setup' ' + git rev-list --all >rla +' + +test_perf 'cat-file --batch-check' ' + git cat-file --batch-check <rla +' + +test_done base-commit: 715d08a9e51251ad8290b181b6ac3b9e1f9719d7 -- gitgitgadget
