[PATCH] pack-objects: Prefer shallower deltas if the size is equal
- From
Brian Downing <bdowning@lavos.net>
- Date
- Jul 9, 2007, 04:45 UTC
- Message-ID
- <20070709044521.GI4087@lavos.net>
- In-Reply-To
- <20070709044326.GH4087@lavos.net>
Change "try_delta" so that if it finds a delta that has the same size but shallower depth than the existing delta, it will prefer the shallower one. This makes certain delta trees vastly less deep.
Signed-off-by: Brian Downing <bdowning@lavos.net> --- builtin-pack-objects.c | 8 +++++++- 1 files changed, 7 insertions(+), 1 deletions(-)
diff --git a/builtin-pack-objects.c b/builtin-pack-objects.c index 3d396ca..54b9d26 100644 --- a/builtin-pack-objects.c +++ b/builtin-pack-objects.c @@ -1337,7 +1337,7 @@ static int try_delta(struct unpacked *trg, struct unpacked *src, if (max_size == 0) return 0; if (trg_entry->delta && trg_entry->delta_size <= max_size) - max_size = trg_entry->delta_size-1; + max_size = trg_entry->delta_size; src_size = src_entry->size; sizediff = src_size < trg_size ? trg_size - src_size : 0; if (sizediff >= max_size) @@ -1371,6 +1371,12 @@ static int try_delta(struct unpacked *trg, struct unpacked *src, return 0; if (trg_entry->delta_data) { + /* Prefer only shallower same-sized deltas. */ + if (delta_size == trg_entry->delta_size && + src_entry->depth + 1 >= trg_entry->depth) { + free(delta_buf); + return 0; + } delta_cache_size -= trg_entry->delta_size; free(trg_entry->delta_data); }
-- 1.5.2.GIT