Subject: [PATCH 11/11] pack-objects: increase pack file limit to 4096

From: Nguyễn Thái Ngọc Duy <[email-masked]>
Date: Thu, 1 Mar 2018 16:10:52 +0700

When OE_IN_PACK_BITS was added, we didn't have many bits left to spare
so the max number of packs that pack-objects could handle was limited
to 256. Now we have more spare bits, let's increase it to 4096 to be
on the safe side. If you have more than this many packs, you may need
to reconsider if you're still sane.

Increasing this also increases memory a bit because in_pack[] array in
packing_data is bigger, roughly 32kb, which is insignificant in
pack-objects context.

Signed-off-by: Nguyễn Thái Ngọc Duy <[email-masked]>
---
 pack-objects.h | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/pack-objects.h b/pack-objects.h
index 52087b32e5..ec4eba4ee4 100644
--- a/pack-objects.h
+++ b/pack-objects.h
@@ -3,7 +3,7 @@
 
 #define OE_DFS_STATE_BITS 2
 #define OE_DEPTH_BITS 12
-#define OE_IN_PACK_BITS 8
+#define OE_IN_PACK_BITS 12
 
 #define IN_PACK_POS(to_pack, obj) \
 	(to_pack)->in_pack_pos[(struct object_entry *)(obj) - (to_pack)->objects]
@@ -24,6 +24,11 @@ enum dfs_state {
 	DFS_NUM_STATES
 };
 
+/*
+ * The size of struct nearly determines pack-objects's memory
+ * consumption. This struct is packed tight for that reason. When you
+ * add or reorder something in this struct, think a bit about this.
+ */
 struct object_entry {
 	struct pack_idx_entry idx;
 	unsigned long size;	/* uncompressed size */
@@ -51,7 +56,7 @@ struct object_entry {
 	unsigned filled:1; /* assigned write-order */
 	unsigned dfs_state:OE_DFS_STATE_BITS;
 
-	/* XXX 12 bits hole, try to pack */
+	/* XXX 8 bits hole, try to pack */
 
 	unsigned depth:OE_DEPTH_BITS;
 
-- 
2.16.1.435.g8f24da2e1a