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>

1 files changed, 35 insertions, 14 deletions

diff --git a/builtin/repack.c b/builtin/repack.c
index 593c18d..b85483a 100644
--- 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)