diff options
| -rw-r--r-- | Documentation/config.txt | 5 | ||||
| -rw-r--r-- | builtin-pack-objects.c | 69 |
2 files changed, 59 insertions, 15 deletions
diff --git a/Documentation/config.txt b/Documentation/config.txt index 3d8f03dfe..ab0f8f486 100644 --- a/Documentation/config.txt +++ b/Documentation/config.txt @@ -567,6 +567,11 @@ pack.compression:: slowest. If not set, defaults to core.compression. If that is not set, defaults to -1. +pack.deltaCacheSize:: + The maxium memory in bytes used for caching deltas in + gitlink:git-pack-objects[1]. + A value of 0 means no limit. Defaults to 0. + pull.octopus:: The default merge strategy to use when pulling multiple branches at once. diff --git a/builtin-pack-objects.c b/builtin-pack-objects.c index 17627b34e..9f035ba8e 100644 --- a/builtin-pack-objects.c +++ b/builtin-pack-objects.c @@ -36,6 +36,7 @@ struct object_entry { struct object_entry *delta_sibling; /* other deltified objects who * uses the same base as me */ + void *delta_data; /* cached delta (uncompressed) */ unsigned long delta_size; /* delta data size (uncompressed) */ enum object_type type; enum object_type in_pack_type; /* could be delta */ @@ -76,6 +77,9 @@ static struct progress progress_state; static int pack_compression_level = Z_DEFAULT_COMPRESSION; static int pack_compression_seen; +static unsigned long delta_cache_size = 0; +static unsigned long max_delta_cache_size = 0; + /* * The object names in objects array are hashed with this hashtable, * to help looking up the entry by object name. @@ -405,24 +409,31 @@ static unsigned long write_object(struct sha1file *f, z_stream stream; unsigned long maxsize; void *out; - buf = read_sha1_file(entry->sha1, &type, &size); - if (!buf) - die("unable to read %s", sha1_to_hex(entry->sha1)); - if (size != entry->size) - die("object %s size inconsistency (%lu vs %lu)", - sha1_to_hex(entry->sha1), size, entry->size); - if (usable_delta) { - buf = delta_against(buf, size, entry); + if (entry->delta_data && usable_delta) { + buf = entry->delta_data; size = entry->delta_size; obj_type = (allow_ofs_delta && entry->delta->offset) ? OBJ_OFS_DELTA : OBJ_REF_DELTA; } else { - /* - * recover real object type in case - * check_object() wanted to re-use a delta, - * but we couldn't since base was in previous split pack - */ - obj_type = type; + buf = read_sha1_file(entry->sha1, &type, &size); + if (!buf) + die("unable to read %s", sha1_to_hex(entry->sha1)); + if (size != entry->size) + die("object %s size inconsistency (%lu vs %lu)", + sha1_to_hex(entry->sha1), size, entry->size); + if (usable_delta) { + buf = delta_against(buf, size, entry); + size = entry->delta_size; + obj_type = (allow_ofs_delta && entry->delta->offset) ? + OBJ_OFS_DELTA : OBJ_REF_DELTA; + } else { + /* + * recover real object type in case + * check_object() wanted to re-use a delta, + * but we couldn't since base was in previous split pack + */ + obj_type = type; + } } /* compress the data to store and put compressed length in datalen */ memset(&stream, 0, sizeof(stream)); @@ -1385,6 +1396,20 @@ struct unpacked { struct delta_index *index; }; +static int delta_cacheable(struct unpacked *trg, struct unpacked *src, + unsigned long src_size, unsigned long trg_size, + unsigned long delta_size) +{ + if (max_delta_cache_size && delta_cache_size + delta_size > max_delta_cache_size) + return 0; + + /* cache delta, if objects are large enough compared to delta size */ + if ((src_size >> 20) + (trg_size >> 21) > (delta_size >> 10)) + return 1; + + return 0; +} + /* * We search for deltas _backwards_ in a list sorted by type and * by size, so that we see progressively smaller and smaller files. @@ -1466,10 +1491,20 @@ static int try_delta(struct unpacked *trg, struct unpacked *src, if (!delta_buf) return 0; + if (trg_entry->delta_data) { + delta_cache_size -= trg_entry->delta_size; + free(trg_entry->delta_data); + } + trg_entry->delta_data = 0; trg_entry->delta = src_entry; trg_entry->delta_size = delta_size; trg_entry->depth = src_entry->depth + 1; - free(delta_buf); + + if (delta_cacheable(src, trg, src_size, trg_size, delta_size)) { + trg_entry->delta_data = xrealloc(delta_buf, delta_size); + delta_cache_size += trg_entry->delta_size; + } else + free(delta_buf); return 1; } @@ -1615,6 +1650,10 @@ static int git_pack_config(const char *k, const char *v) pack_compression_seen = 1; return 0; } + if (!strcmp(k, "pack.deltacachesize")) { + max_delta_cache_size = git_config_int(k, v); + return 0; + } return git_default_config(k, v); } |