Message ID | c329a8ddc087c9b74f673005f8b1e8769816ab9a.1580430057.git.me@ttaylorr.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | builtin/commit-graph.c: new split/merge options | expand |
On 1/30/2020 7:28 PM, Taylor Blau wrote: > In the previous commit, we introduced '--[no-]merge', and alluded to the > fact that '--merge' would be useful for callers who wish to always > trigger a merge of an incremental chain. > > There is a problem with the above approach, which is that there is no > way to specify to the commit-graph builtin that a caller only wants to > include commits already in the graph. One can specify '--input=append' > to include all commits in the existing graphs, but the absence of > '--input=stdin-{commits,packs}' causes the builtin to call > 'fill_oids_from_all_packs()'. > > Passing '--input=reachable' (as in 'git commit-graph write > --split=merge-all --input=reachable --input=append') works around this > issue by making '--input=reachable' effectively a no-op, but this can be > prohibitively expensive in large repositories, making it an undesirable > choice for some users. > > Teach '--input=none' as an option to behave as if '--input=append' were > given, but to consider no other sources in addition. The code change looks good. > +test_expect_success '--split=no-merge, --input=none writes nothing' ' > + test_when_finished rm -rf a graphs.before graphs.after && > + rm -rf $graphdir && > + git reset --hard commits/2 && > + git rev-list -1 HEAD~1 >a && > + git commit-graph write --split=no-merge --input=stdin-commits <a && > + ls $graphdir/graph-*.graph >graphs.before && > + test_line_count = 1 $graphdir/commit-graph-chain && > + git commit-graph write --split --input=none && > + ls $graphdir/graph-*.graph >graphs.after && > + test_cmp graphs.before graphs.after > +' > + > +test_expect_success '--split=merge-all, --input=none merges the chain' ' > + test_when_finished rm -rf a b && > + rm -rf $graphdir && > + git reset --hard commits/2 && > + git rev-list -1 HEAD~1 >a && > + git rev-list -1 HEAD >b && > + git commit-graph write --split=no-merge --input=stdin-commits <a && > + git commit-graph write --split=no-merge --input=stdin-commits <b && > + test_line_count = 2 $graphdir/commit-graph-chain && > + git commit-graph write --split=merge-all --input=none && > + test_line_count = 1 $graphdir/commit-graph-chain > +' And these tests demonstrate the value quite clearly. Thanks! -Stolee
On Fri, 31 Jan 2020 at 01:30, Taylor Blau <me@ttaylorr.com> wrote: > In the previous commit, we introduced '--[no-]merge', and alluded to the > fact that '--merge' would be useful for callers who wish to always > trigger a merge of an incremental chain. Hmmm. So it looks like you've already had similar thoughts as I did about patch 1/3. At some point, you had a separate `--merge=...` option, then later made that `--split=...`. :-) Could you say something about why you changed your mind? > There is a problem with the above approach, which is that there is no > way to specify to the commit-graph builtin that a caller only wants to > include commits already in the graph. One can specify '--input=append' > to include all commits in the existing graphs, but the absence of > '--input=stdin-{commits,packs}' causes the builtin to call > 'fill_oids_from_all_packs()'. (Use one of those options with an empty stdin? Anyway, let's read on.) > Passing '--input=reachable' (as in 'git commit-graph write > --split=merge-all --input=reachable --input=append') works around this > issue by making '--input=reachable' effectively a no-op, but this can be > prohibitively expensive in large repositories, making it an undesirable > choice for some users. > > Teach '--input=none' as an option to behave as if '--input=append' were > given, but to consider no other sources in addition. `--input=none` almost makes me wonder if it should produce an empty commit-graph. But there wouldn't be much point in that... I guess another way of defining this would be that it "uses no input, and implies `--append`". > This, in conjunction with the option introduced in the previous patch > offers the convenient way to force the commit-graph machinery to > condense a chain of incrementals without requiring any new commits: > > $ git commit-graph write --split=merge-all --input=none Right. > --- a/Documentation/git-commit-graph.txt > +++ b/Documentation/git-commit-graph.txt > @@ -39,24 +39,29 @@ COMMANDS > -------- > 'write':: > > -Write a commit-graph file based on the commits found in packfiles. > +Write a commit-graph file based on the commits specified: > +* With the `--input=stdin-packs` option, generate the new commit graph > +by walking objects only in the specified pack-indexes. (Cannot be > +combined with `--input=stdin-commits` or `--input=reachable`.) > + > -With the `--input=stdin-packs` option, generate the new commit graph by > -walking objects only in the specified pack-indexes. (Cannot be combined > -with `--input=stdin-commits` or `--input=reachable`.) > -+ > -With the `--input=stdin-commits` option, generate the new commit graph > +* With the `--input=stdin-commits` option, generate the new commit graph > by walking commits starting at the commits specified in stdin as a list > of OIDs in hex, one OID per line. (Cannot be combined with > `--input=stdin-packs` or `--input=reachable`.) > + > -With the `--input=reachable` option, generate the new commit graph by > +* With the `--input=reachable` option, generate the new commit graph by > walking commits starting at all refs. (Cannot be combined with > `--input=stdin-commits` or `--input=stdin-packs`.) > + > -With the `--input=append` option, include all commits that are present > +* With the `--input=append` option, include all commits that are present > in the existing commit-graph file. Do these changes above really belong in this commit? > +* With the `--input=none` option, behave as if `input=append` were > +given, but do not walk other packs to find additional commits. > + > +If none of the above options are given, then commits found in > +packfiles are specified. "specified"? Plus, that also happens for `--input=append` right? (It really seems like "append" is an odd one among all the inputs.) > N_("git commit-graph write [--object-dir <objdir>] [--append] " > - "[--split[=<strategy>]] [--input=<reachable|stdin-packs|stdin-commits>] " > + "[--split[=<strategy>]] " > + "[--input=<reachable|stdin-packs|stdin-commits|none>] " > "[--[no-]progress] <split options>"), Hmm, you've left "--append" the old way. Martin
On Fri, Jan 31, 2020 at 08:45:59PM +0100, Martin Ågren wrote: > On Fri, 31 Jan 2020 at 01:30, Taylor Blau <me@ttaylorr.com> wrote: > > In the previous commit, we introduced '--[no-]merge', and alluded to the > > fact that '--merge' would be useful for callers who wish to always > > trigger a merge of an incremental chain. > > Hmmm. So it looks like you've already had similar thoughts as I did > about patch 1/3. At some point, you had a separate `--merge=...` option, > then later made that `--split=...`. :-) Could you say something about why > you changed your mind? Heh :-). Left overs from an earlier version of this series. I think that I already talked about why this was changed further up in the thread. > > There is a problem with the above approach, which is that there is no > > way to specify to the commit-graph builtin that a caller only wants to > > include commits already in the graph. One can specify '--input=append' > > to include all commits in the existing graphs, but the absence of > > '--input=stdin-{commits,packs}' causes the builtin to call > > 'fill_oids_from_all_packs()'. > > (Use one of those options with an empty stdin? Anyway, let's read on.) > > > Passing '--input=reachable' (as in 'git commit-graph write > > --split=merge-all --input=reachable --input=append') works around this > > issue by making '--input=reachable' effectively a no-op, but this can be > > prohibitively expensive in large repositories, making it an undesirable > > choice for some users. > > > > Teach '--input=none' as an option to behave as if '--input=append' were > > given, but to consider no other sources in addition. > > `--input=none` almost makes me wonder if it should produce an empty > commit-graph. But there wouldn't be much point in that... I guess > another way of defining this would be that it "uses no input, and > implies `--append`". I suppose, although (like you) I can't imagine why anybody would want to do that. > > This, in conjunction with the option introduced in the previous patch > > offers the convenient way to force the commit-graph machinery to > > condense a chain of incrementals without requiring any new commits: > > > > $ git commit-graph write --split=merge-all --input=none > > Right. > > > --- a/Documentation/git-commit-graph.txt > > +++ b/Documentation/git-commit-graph.txt > > @@ -39,24 +39,29 @@ COMMANDS > > -------- > > 'write':: > > > > -Write a commit-graph file based on the commits found in packfiles. > > +Write a commit-graph file based on the commits specified: > > +* With the `--input=stdin-packs` option, generate the new commit graph > > +by walking objects only in the specified pack-indexes. (Cannot be > > +combined with `--input=stdin-commits` or `--input=reachable`.) > > + > > -With the `--input=stdin-packs` option, generate the new commit graph by > > -walking objects only in the specified pack-indexes. (Cannot be combined > > -with `--input=stdin-commits` or `--input=reachable`.) > > -+ > > -With the `--input=stdin-commits` option, generate the new commit graph > > +* With the `--input=stdin-commits` option, generate the new commit graph > > by walking commits starting at the commits specified in stdin as a list > > of OIDs in hex, one OID per line. (Cannot be combined with > > `--input=stdin-packs` or `--input=reachable`.) > > + > > -With the `--input=reachable` option, generate the new commit graph by > > +* With the `--input=reachable` option, generate the new commit graph by > > walking commits starting at all refs. (Cannot be combined with > > `--input=stdin-commits` or `--input=stdin-packs`.) > > + > > -With the `--input=append` option, include all commits that are present > > +* With the `--input=append` option, include all commits that are present > > in the existing commit-graph file. > > Do these changes above really belong in this commit? I think so. My thought here was to leave this documentation as-is until this patch, when adding '--input=none' would... somehow change this, but trying to construct a reply, I can't seem to come up with why I thought that this was a good idea in the first place ;-). > > +* With the `--input=none` option, behave as if `input=append` were > > +given, but do not walk other packs to find additional commits. > > + > > +If none of the above options are given, then commits found in > > +packfiles are specified. > > "specified"? Plus, that also happens for `--input=append` right? (It > really seems like "append" is an odd one among all the inputs.) I reworded this slightly to not use "specified", which I agree is indeed weird. > > > N_("git commit-graph write [--object-dir <objdir>] [--append] " > > - "[--split[=<strategy>]] [--input=<reachable|stdin-packs|stdin-commits>] " > > + "[--split[=<strategy>]] " > > + "[--input=<reachable|stdin-packs|stdin-commits|none>] " > > "[--[no-]progress] <split options>"), > > Hmm, you've left "--append" the old way. Fixed, and thanks for noticing. > > Martin Thanks, Taylor
diff --git a/Documentation/git-commit-graph.txt b/Documentation/git-commit-graph.txt index cbf80226e9..d380c42e82 100644 --- a/Documentation/git-commit-graph.txt +++ b/Documentation/git-commit-graph.txt @@ -39,24 +39,29 @@ COMMANDS -------- 'write':: -Write a commit-graph file based on the commits found in packfiles. +Write a commit-graph file based on the commits specified: +* With the `--input=stdin-packs` option, generate the new commit graph +by walking objects only in the specified pack-indexes. (Cannot be +combined with `--input=stdin-commits` or `--input=reachable`.) + -With the `--input=stdin-packs` option, generate the new commit graph by -walking objects only in the specified pack-indexes. (Cannot be combined -with `--input=stdin-commits` or `--input=reachable`.) -+ -With the `--input=stdin-commits` option, generate the new commit graph +* With the `--input=stdin-commits` option, generate the new commit graph by walking commits starting at the commits specified in stdin as a list of OIDs in hex, one OID per line. (Cannot be combined with `--input=stdin-packs` or `--input=reachable`.) + -With the `--input=reachable` option, generate the new commit graph by +* With the `--input=reachable` option, generate the new commit graph by walking commits starting at all refs. (Cannot be combined with `--input=stdin-commits` or `--input=stdin-packs`.) + -With the `--input=append` option, include all commits that are present +* With the `--input=append` option, include all commits that are present in the existing commit-graph file. + +* With the `--input=none` option, behave as if `input=append` were +given, but do not walk other packs to find additional commits. + +If none of the above options are given, then commits found in +packfiles are specified. ++ With the `--split[=<strategy>]` option, write the commit-graph as a chain of multiple commit-graph files stored in `<dir>/info/commit-graphs`. Commit-graph layers are merged based on the diff --git a/builtin/commit-graph.c b/builtin/commit-graph.c index 03d815e652..937b98e99e 100644 --- a/builtin/commit-graph.c +++ b/builtin/commit-graph.c @@ -10,7 +10,8 @@ static char const * const builtin_commit_graph_usage[] = { N_("git commit-graph verify [--object-dir <objdir>] [--shallow] [--[no-]progress]"), N_("git commit-graph write [--object-dir <objdir>] [--append] " - "[--split[=<strategy>]] [--input=<reachable|stdin-packs|stdin-commits>] " + "[--split[=<strategy>]] " + "[--input=<reachable|stdin-packs|stdin-commits|none>] " "[--[no-]progress] <split options>"), NULL }; @@ -22,7 +23,8 @@ static const char * const builtin_commit_graph_verify_usage[] = { static const char * const builtin_commit_graph_write_usage[] = { N_("git commit-graph write [--object-dir <objdir>] [--append] " - "[--split[=<strategy>]] [--input=<reachable|stdin-packs|stdin-commits>] " + "[--split[=<strategy>]] " + "[--input=<reachable|stdin-packs|stdin-commits|none>] " "[--[no-]progress] <split options>"), NULL }; @@ -31,7 +33,8 @@ enum commit_graph_input { COMMIT_GRAPH_INPUT_REACHABLE = (1 << 1), COMMIT_GRAPH_INPUT_STDIN_PACKS = (1 << 2), COMMIT_GRAPH_INPUT_STDIN_COMMITS = (1 << 3), - COMMIT_GRAPH_INPUT_APPEND = (1 << 4) + COMMIT_GRAPH_INPUT_APPEND = (1 << 4), + COMMIT_GRAPH_INPUT_NONE = (1 << 5) }; static struct opts_commit_graph { @@ -59,6 +62,8 @@ static int option_parse_input(const struct option *opt, const char *arg, *to |= COMMIT_GRAPH_INPUT_STDIN_COMMITS; else if (!strcmp(arg, "append")) *to |= COMMIT_GRAPH_INPUT_APPEND; + else if (!strcmp(arg, "none")) + *to |= (COMMIT_GRAPH_INPUT_APPEND | COMMIT_GRAPH_INPUT_NONE); else die(_("unrecognized --input source, %s"), arg); return 0; @@ -211,6 +216,8 @@ static int graph_write(int argc, const char **argv) opts.obj_dir = get_object_directory(); if (opts.input & COMMIT_GRAPH_INPUT_APPEND) flags |= COMMIT_GRAPH_WRITE_APPEND; + if (opts.input & COMMIT_GRAPH_INPUT_NONE) + flags |= COMMIT_GRAPH_WRITE_NO_INPUT; if (opts.split) flags |= COMMIT_GRAPH_WRITE_SPLIT; if (opts.progress) diff --git a/commit-graph.c b/commit-graph.c index 02e6ad9d1f..a5d7624073 100644 --- a/commit-graph.c +++ b/commit-graph.c @@ -808,7 +808,8 @@ struct write_commit_graph_context { unsigned append:1, report_progress:1, split:1, - check_oids:1; + check_oids:1, + no_input:1; const struct split_commit_graph_opts *split_opts; }; @@ -1802,6 +1803,7 @@ int write_commit_graph(struct object_directory *odb, ctx->split = flags & COMMIT_GRAPH_WRITE_SPLIT ? 1 : 0; ctx->check_oids = flags & COMMIT_GRAPH_WRITE_CHECK_OIDS ? 1 : 0; ctx->split_opts = split_opts; + ctx->no_input = flags & COMMIT_GRAPH_WRITE_NO_INPUT ? 1 : 0; if (ctx->split) { struct commit_graph *g; @@ -1860,7 +1862,7 @@ int write_commit_graph(struct object_directory *odb, goto cleanup; } - if (!pack_indexes && !commit_hex) + if (!ctx->no_input && !pack_indexes && !commit_hex) fill_oids_from_all_packs(ctx); close_reachable(ctx); diff --git a/commit-graph.h b/commit-graph.h index dadcc03808..dd8c00a2d8 100644 --- a/commit-graph.h +++ b/commit-graph.h @@ -81,7 +81,8 @@ enum commit_graph_write_flags { COMMIT_GRAPH_WRITE_PROGRESS = (1 << 1), COMMIT_GRAPH_WRITE_SPLIT = (1 << 2), /* Make sure that each OID in the input is a valid commit OID. */ - COMMIT_GRAPH_WRITE_CHECK_OIDS = (1 << 3) + COMMIT_GRAPH_WRITE_CHECK_OIDS = (1 << 3), + COMMIT_GRAPH_WRITE_NO_INPUT = (1 << 4) }; enum commit_graph_split_flags { diff --git a/t/t5324-split-commit-graph.sh b/t/t5324-split-commit-graph.sh index dd74295885..296b5a9185 100755 --- a/t/t5324-split-commit-graph.sh +++ b/t/t5324-split-commit-graph.sh @@ -369,4 +369,30 @@ test_expect_success '--split=no-merge always writes an incremental' ' test_line_count = 2 $graphdir/commit-graph-chain ' +test_expect_success '--split=no-merge, --input=none writes nothing' ' + test_when_finished rm -rf a graphs.before graphs.after && + rm -rf $graphdir && + git reset --hard commits/2 && + git rev-list -1 HEAD~1 >a && + git commit-graph write --split=no-merge --input=stdin-commits <a && + ls $graphdir/graph-*.graph >graphs.before && + test_line_count = 1 $graphdir/commit-graph-chain && + git commit-graph write --split --input=none && + ls $graphdir/graph-*.graph >graphs.after && + test_cmp graphs.before graphs.after +' + +test_expect_success '--split=merge-all, --input=none merges the chain' ' + test_when_finished rm -rf a b && + rm -rf $graphdir && + git reset --hard commits/2 && + git rev-list -1 HEAD~1 >a && + git rev-list -1 HEAD >b && + git commit-graph write --split=no-merge --input=stdin-commits <a && + git commit-graph write --split=no-merge --input=stdin-commits <b && + test_line_count = 2 $graphdir/commit-graph-chain && + git commit-graph write --split=merge-all --input=none && + test_line_count = 1 $graphdir/commit-graph-chain +' + test_done
In the previous commit, we introduced '--[no-]merge', and alluded to the fact that '--merge' would be useful for callers who wish to always trigger a merge of an incremental chain. There is a problem with the above approach, which is that there is no way to specify to the commit-graph builtin that a caller only wants to include commits already in the graph. One can specify '--input=append' to include all commits in the existing graphs, but the absence of '--input=stdin-{commits,packs}' causes the builtin to call 'fill_oids_from_all_packs()'. Passing '--input=reachable' (as in 'git commit-graph write --split=merge-all --input=reachable --input=append') works around this issue by making '--input=reachable' effectively a no-op, but this can be prohibitively expensive in large repositories, making it an undesirable choice for some users. Teach '--input=none' as an option to behave as if '--input=append' were given, but to consider no other sources in addition. This, in conjunction with the option introduced in the previous patch offers the convenient way to force the commit-graph machinery to condense a chain of incrementals without requiring any new commits: $ git commit-graph write --split=merge-all --input=none Signed-off-by: Taylor Blau <me@ttaylorr.com> --- Documentation/git-commit-graph.txt | 21 +++++++++++++-------- builtin/commit-graph.c | 13 ++++++++++--- commit-graph.c | 6 ++++-- commit-graph.h | 3 ++- t/t5324-split-commit-graph.sh | 26 ++++++++++++++++++++++++++ 5 files changed, 55 insertions(+), 14 deletions(-)