builtin/repack.c: allow configuring cruft pack generation

In servers which set the pack.window configuration to a large value, we
can wind up spending quite a lot of time finding new bases when breaking
delta chains between reachable and unreachable objects while generating
a cruft pack.

Introduce a handful of `repack.cruft*` configuration variables to
control the parameters used by pack-objects when generating a cruft
pack.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/Documentation/config/repack.txt b/Documentation/config/repack.txt
index 41ac6953c87eb55f14b01471a5b6013bb318859e..c79af6d7b8b5d7dc03329480d8d418839fe3fef7 100644 (file)
--- a/Documentation/config/repack.txt
+++ b/Documentation/config/repack.txt
@@ -30,3 +30,12 @@ repack.updateServerInfo::
        If set to false, linkgit:git-repack[1] will not run
        linkgit:git-update-server-info[1]. Defaults to true. Can be overridden
        when true by the `-n` option of linkgit:git-repack[1].
+
+repack.cruftWindow::
+repack.cruftWindowMemory::
+repack.cruftDepth::
+repack.cruftThreads::
+       Parameters used by linkgit:git-pack-objects[1] when generating
+       a cruft pack and the respective parameters are not given over
+       the command line. See similarly named `pack.*` configuration
+       variables for defaults and meaning.

diff --git a/builtin/repack.c b/builtin/repack.c
index 593c18d4e8521f4744d0e6af68fc47f5acac784c..b85483a1484ea5ec804cb4d600581970e5edc1f6 100644 (file)
--- a/builtin/repack.c
+++ b/builtin/repack.c
@@ -41,9 +41,21 @@ static const char incremental_bitmap_conflict_error[] = N_(
 "--no-write-bitmap-index or disable the pack.writebitmaps configuration."
 );
 
+struct pack_objects_args {
+       const char *window;
+       const char *window_memory;
+       const char *depth;
+       const char *threads;
+       const char *max_pack_size;
+       int no_reuse_delta;
+       int no_reuse_object;
+       int quiet;
+       int local;
+};
 
 static int repack_config(const char *var, const char *value, void *cb)
 {
+       struct pack_objects_args *cruft_po_args = cb;
        if (!strcmp(var, "repack.usedeltabaseoffset")) {
                delta_base_offset = git_config_bool(var, value);
                return 0;
@@ -65,6 +77,14 @@ static int repack_config(const char *var, const char *value, void *cb)
                run_update_server_info = git_config_bool(var, value);
                return 0;
        }
+       if (!strcmp(var, "repack.cruftwindow"))
+               return git_config_string(&cruft_po_args->window, var, value);
+       if (!strcmp(var, "repack.cruftwindowmemory"))
+               return git_config_string(&cruft_po_args->window_memory, var, value);
+       if (!strcmp(var, "repack.cruftdepth"))
+               return git_config_string(&cruft_po_args->depth, var, value);
+       if (!strcmp(var, "repack.cruftthreads"))
+               return git_config_string(&cruft_po_args->threads, var, value);
        return git_default_config(var, value, cb);
 }
 
@@ -157,18 +177,6 @@ static void remove_redundant_pack(const char *dir_name, const char *base_name)
        strbuf_release(&buf);
 }
 
-struct pack_objects_args {
-       const char *window;
-       const char *window_memory;
-       const char *depth;
-       const char *threads;
-       const char *max_pack_size;
-       int no_reuse_delta;
-       int no_reuse_object;
-       int quiet;
-       int local;
-};
-
 static void prepare_pack_objects(struct child_process *cmd,
                                 const struct pack_objects_args *args)
 {
@@ -692,6 +700,7 @@ int cmd_repack(int argc, const char **argv, const char *prefix)
        int keep_unreachable = 0;
        struct string_list keep_pack_list = STRING_LIST_INIT_NODUP;
        struct pack_objects_args po_args = {NULL};
+       struct pack_objects_args cruft_po_args = {NULL};
        int geometric_factor = 0;
        int write_midx = 0;
 
@@ -746,7 +755,7 @@ int cmd_repack(int argc, const char **argv, const char *prefix)
                OPT_END()
        };
 
-       git_config(repack_config, NULL);
+       git_config(repack_config, &cruft_po_args);
 
        argc = parse_options(argc, argv, prefix, builtin_repack_options,
                                git_repack_usage, 0);
@@ -921,7 +930,19 @@ int cmd_repack(int argc, const char **argv, const char *prefix)
                if (*pack_prefix == '/')
                        pack_prefix++;
 
-               ret = write_cruft_pack(&po_args, pack_prefix, &names,
+               if (!cruft_po_args.window)
+                       cruft_po_args.window = po_args.window;
+               if (!cruft_po_args.window_memory)
+                       cruft_po_args.window_memory = po_args.window_memory;
+               if (!cruft_po_args.depth)
+                       cruft_po_args.depth = po_args.depth;
+               if (!cruft_po_args.threads)
+                       cruft_po_args.threads = po_args.threads;
+
+               cruft_po_args.local = po_args.local;
+               cruft_po_args.quiet = po_args.quiet;
+
+               ret = write_cruft_pack(&cruft_po_args, pack_prefix, &names,
                                       &existing_nonkept_packs,
                                       &existing_kept_packs);
                if (ret)

diff --git a/t/t5329-pack-objects-cruft.sh b/t/t5329-pack-objects-cruft.sh
index 067c50af38cf254562538225ae57023f4834e147..c82f973b41f437a050555687a7dfe56f984bdbb5 100755 (executable)
--- a/t/t5329-pack-objects-cruft.sh
+++ b/t/t5329-pack-objects-cruft.sh
@@ -565,4 +565,87 @@ test_expect_success 'cruft repack ignores pack.packSizeLimit' '
        )
 '
 
+test_expect_success 'cruft repack respects repack.cruftWindow' '
+       git init repo &&
+       test_when_finished "rm -fr repo" &&
+       (
+               cd repo &&
+
+               test_commit base &&
+
+               GIT_TRACE2_EVENT=$(pwd)/event.trace \
+               git -c pack.window=1 -c repack.cruftWindow=2 repack \
+                      --cruft --window=3 &&
+
+               grep "pack-objects.*--window=2.*--cruft" event.trace
+       )
+'
+
+test_expect_success 'cruft repack respects --window by default' '
+       git init repo &&
+       test_when_finished "rm -fr repo" &&
+       (
+               cd repo &&
+
+               test_commit base &&
+
+               GIT_TRACE2_EVENT=$(pwd)/event.trace \
+               git -c pack.window=2 repack --cruft --window=3 &&
+
+               grep "pack-objects.*--window=3.*--cruft" event.trace
+       )
+'
+
+test_expect_success 'cruft repack respects --quiet' '
+       git init repo &&
+       test_when_finished "rm -fr repo" &&
+       (
+               cd repo &&
+
+               test_commit base &&
+               GIT_PROGRESS_DELAY=0 git repack --cruft --quiet 2>err &&
+               test_must_be_empty err
+       )
+'
+
+test_expect_success 'cruft --local drops unreachable objects' '
+       git init alternate &&
+       git init repo &&
+       test_when_finished "rm -fr alternate repo" &&
+
+       test_commit -C alternate base &&
+       # Pack all objects in alterate so that the cruft repack in "repo" sees
+       # the object it dropped due to `--local` as packed. Otherwise this
+       # object would not appear packed anywhere (since it is not packed in
+       # alternate and likewise not part of the cruft pack in the other repo
+       # because of `--local`).
+       git -C alternate repack -ad &&
+
+       (
+               cd repo &&
+
+               object="$(git -C ../alternate rev-parse HEAD:base.t)" &&
+               git -C ../alternate cat-file -p $object >contents &&
+
+               # Write some reachable objects and two unreachable ones: one
+               # that the alternate has and another that is unique.
+               test_commit other &&
+               git hash-object -w -t blob contents &&
+               cruft="$(echo cruft | git hash-object -w -t blob --stdin)" &&
+
+               ( cd ../alternate/.git/objects && pwd ) \
+                      >.git/objects/info/alternates &&
+
+               test_path_is_file $objdir/$(test_oid_to_path $cruft) &&
+               test_path_is_file $objdir/$(test_oid_to_path $object) &&
+
+               git repack -d --cruft --local &&
+
+               test-tool pack-mtimes "$(basename $(ls $packdir/pack-*.mtimes))" \
+                      >objects &&
+               ! grep $object objects &&
+               grep $cruft objects
+       )
+'
+
 test_done