diff mbox series

[v4,08/12] pack-objects: introduce pack.allowPackReuse

Message ID 20191218112547.4974-9-chriscool@tuxfamily.org (mailing list archive)
State New, archived
Headers show
Series Rewrite packfile reuse code | expand

Commit Message

Christian Couder Dec. 18, 2019, 11:25 a.m. UTC 
From: Jeff King <peff@peff.net>

Let's make it possible to configure if we want pack reuse or not.

The main reason it might not be wanted is probably debugging and
performance testing, though pack reuse _might_ cause larger packs,
because we wouldn't consider the reused objects as bases for
finding new deltas.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
---
 Documentation/config/pack.txt | 7 +++++++
 builtin/pack-objects.c        | 8 +++++++-
 2 files changed, 14 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/Documentation/config/pack.txt b/Documentation/config/pack.txt
index 1d66f0c992..0dac580581 100644
--- a/Documentation/config/pack.txt
+++ b/Documentation/config/pack.txt
@@ -27,6 +27,13 @@  Note that changing the compression level will not automatically recompress
 all existing objects. You can force recompression by passing the -F option
 to linkgit:git-repack[1].
 
+pack.allowPackReuse::
+	When true, and when reachability bitmaps are enabled,
+	pack-objects will try to send parts of the bitmapped packfile
+	verbatim. This can reduce memory and CPU usage to serve fetches,
+	but might result in sending a slightly larger pack. Defaults to
+	true.
+
 pack.island::
 	An extended regular expression configuring a set of delta
 	islands. See "DELTA ISLANDS" in linkgit:git-pack-objects[1]
diff --git a/builtin/pack-objects.c b/builtin/pack-objects.c
index 369f46fbc5..801e23dfe7 100644
--- a/builtin/pack-objects.c
+++ b/builtin/pack-objects.c
@@ -96,6 +96,7 @@  static off_t reuse_packfile_offset;
 
 static int use_bitmap_index_default = 1;
 static int use_bitmap_index = -1;
+static int allow_pack_reuse = 1;
 static enum {
 	WRITE_BITMAP_FALSE = 0,
 	WRITE_BITMAP_QUIET,
@@ -2699,6 +2700,10 @@  static int git_pack_config(const char *k, const char *v, void *cb)
 		use_bitmap_index_default = git_config_bool(k, v);
 		return 0;
 	}
+	if (!strcmp(k, "pack.allowpackreuse")) {
+		allow_pack_reuse = git_config_bool(k, v);
+		return 0;
+	}
 	if (!strcmp(k, "pack.threads")) {
 		delta_search_threads = git_config_int(k, v);
 		if (delta_search_threads < 0)
@@ -3030,7 +3035,8 @@  static void loosen_unused_packed_objects(void)
  */
 static int pack_options_allow_reuse(void)
 {
-	return pack_to_stdout &&
+	return allow_pack_reuse &&
+	       pack_to_stdout &&
 	       allow_ofs_delta &&
 	       !ignore_packed_keep_on_disk &&
 	       !ignore_packed_keep_in_core &&