From: Derrick Stolee <stolee@xxxxxxxxx> In order to debug what is going on during delta calculations, add a --debug-file=<file> option to 'git pack-objects'. This leads to sending a JSON-formatted description of the delta information to that file. Signed-off-by: Derrick Stolee <stolee@xxxxxxxxx> --- builtin/pack-objects.c | 69 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 69 insertions(+) diff --git a/builtin/pack-objects.c b/builtin/pack-objects.c index 5d5a57e6b1f..7d1dd5a6557 100644 --- a/builtin/pack-objects.c +++ b/builtin/pack-objects.c @@ -50,6 +50,9 @@ */ static struct packing_data to_pack; +static FILE *delta_file; +static int delta_file_nr; + static inline struct object_entry *oe_delta( const struct packing_data *pack, const struct object_entry *e) @@ -516,6 +519,14 @@ static unsigned long write_no_reuse_object(struct hashfile *f, struct object_ent hdrlen = encode_in_pack_object_header(header, sizeof(header), type, size); + if (delta_file) { + if (delta_file_nr++) + fprintf(delta_file, ",\n"); + fprintf(delta_file, "\t\t{\n"); + fprintf(delta_file, "\t\t\t\"oid\" : \"%s\",\n", oid_to_hex(&entry->idx.oid)); + fprintf(delta_file, "\t\t\t\"size\" : %"PRIuMAX",\n", datalen); + } + if (type == OBJ_OFS_DELTA) { /* * Deltas with relative base contain an additional @@ -536,6 +547,11 @@ static unsigned long write_no_reuse_object(struct hashfile *f, struct object_ent hashwrite(f, header, hdrlen); hashwrite(f, dheader + pos, sizeof(dheader) - pos); hdrlen += sizeof(dheader) - pos; + if (delta_file) { + fprintf(delta_file, "\t\t\t\"delta_type\" : \"OFS\",\n"); + fprintf(delta_file, "\t\t\t\"offset\" : %"PRIuMAX",\n", ofs); + fprintf(delta_file, "\t\t\t\"delta_base\" : \"%s\",\n", oid_to_hex(&DELTA(entry)->idx.oid)); + } } else if (type == OBJ_REF_DELTA) { /* * Deltas with a base reference contain @@ -550,6 +566,10 @@ static unsigned long write_no_reuse_object(struct hashfile *f, struct object_ent hashwrite(f, header, hdrlen); hashwrite(f, DELTA(entry)->idx.oid.hash, hashsz); hdrlen += hashsz; + if (delta_file) { + fprintf(delta_file, "\t\t\t\"delta_type\" : \"REF\",\n"); + fprintf(delta_file, "\t\t\t\"delta_base\" : \"%s\",\n", oid_to_hex(&DELTA(entry)->idx.oid)); + } } else { if (limit && hdrlen + datalen + hashsz >= limit) { if (st) @@ -559,6 +579,10 @@ static unsigned long write_no_reuse_object(struct hashfile *f, struct object_ent } hashwrite(f, header, hdrlen); } + + if (delta_file) + fprintf(delta_file, "\t\t\t\"reused\" : false\n\t\t}"); + if (st) { datalen = write_large_blob_data(st, f, &entry->idx.oid); close_istream(st); @@ -619,6 +643,14 @@ static off_t write_reuse_object(struct hashfile *f, struct object_entry *entry, return write_no_reuse_object(f, entry, limit, usable_delta); } + if (delta_file) { + if (delta_file_nr++) + fprintf(delta_file, ",\n"); + fprintf(delta_file, "\t\t{\n"); + fprintf(delta_file, "\t\t\t\"oid\" : \"%s\",\n", oid_to_hex(&entry->idx.oid)); + fprintf(delta_file, "\t\t\t\"size\" : %"PRIuMAX",\n", entry_size); + } + if (type == OBJ_OFS_DELTA) { off_t ofs = entry->idx.offset - DELTA(entry)->idx.offset; unsigned pos = sizeof(dheader) - 1; @@ -633,6 +665,12 @@ static off_t write_reuse_object(struct hashfile *f, struct object_entry *entry, hashwrite(f, dheader + pos, sizeof(dheader) - pos); hdrlen += sizeof(dheader) - pos; reused_delta++; + + if (delta_file) { + fprintf(delta_file, "\t\t\t\"delta_type\" : \"OFS\",\n"); + fprintf(delta_file, "\t\t\t\"offset\" : %"PRIuMAX",\n", ofs); + fprintf(delta_file, "\t\t\t\"delta_base\" : \"%s\",\n", oid_to_hex(&DELTA(entry)->idx.oid)); + } } else if (type == OBJ_REF_DELTA) { if (limit && hdrlen + hashsz + datalen + hashsz >= limit) { unuse_pack(&w_curs); @@ -642,6 +680,10 @@ static off_t write_reuse_object(struct hashfile *f, struct object_entry *entry, hashwrite(f, DELTA(entry)->idx.oid.hash, hashsz); hdrlen += hashsz; reused_delta++; + if (delta_file) { + fprintf(delta_file, "\t\t\t\"delta_type\" : \"REF\",\n"); + fprintf(delta_file, "\t\t\t\"delta_base\" : \"%s\",\n", oid_to_hex(&DELTA(entry)->idx.oid)); + } } else { if (limit && hdrlen + datalen + hashsz >= limit) { unuse_pack(&w_curs); @@ -652,6 +694,10 @@ static off_t write_reuse_object(struct hashfile *f, struct object_entry *entry, copy_pack_data(f, p, &w_curs, offset, datalen); unuse_pack(&w_curs); reused++; + + if (delta_file) + fprintf(delta_file, "\t\t\t\"reused\" : true\n\t\t}"); + return hdrlen + datalen; } @@ -1264,6 +1310,11 @@ static void write_pack_file(void) ALLOC_ARRAY(written_list, to_pack.nr_objects); write_order = compute_write_order(); + if (delta_file) { + fprintf(delta_file, "{\n\t\"num_objects\" : %"PRIu32",\n", to_pack.nr_objects); + fprintf(delta_file, "\t\"objects\" : [\n"); + } + do { unsigned char hash[GIT_MAX_RAWSZ]; char *pack_tmp_name = NULL; @@ -1412,6 +1463,9 @@ static void write_pack_file(void) written, nr_result); trace2_data_intmax("pack-objects", the_repository, "write_pack_file/wrote", nr_result); + + if (delta_file) + fprintf(delta_file, "\n\t]\n}"); } static int no_try_delta(const char *path) @@ -4430,6 +4484,7 @@ int cmd_pack_objects(int argc, const char **argv, const char *prefix) struct string_list keep_pack_list = STRING_LIST_INIT_NODUP; struct list_objects_filter_options filter_options = LIST_OBJECTS_FILTER_INIT; + const char *delta_file_name = NULL; struct option pack_objects_options[] = { OPT_CALLBACK_F('q', "quiet", &progress, NULL, @@ -4536,6 +4591,9 @@ int cmd_pack_objects(int argc, const char **argv, const char *prefix) N_("exclude any configured uploadpack.blobpackfileuri with this protocol")), OPT_BOOL(0, "full-name-hash", &use_full_name_hash, N_("optimize delta compression across identical path names over time")), + OPT_STRING(0, "delta-file", &delta_file_name, + N_("filename"), + N_("output delta compression details to the given file")), OPT_END(), }; @@ -4573,6 +4631,12 @@ int cmd_pack_objects(int argc, const char **argv, const char *prefix) if (pack_to_stdout != !base_name || argc) usage_with_options(pack_usage, pack_objects_options); + if (delta_file_name) { + delta_file = fopen(delta_file_name, "w"); + if (!delta_file) + die_errno("failed to open '%s'", delta_file_name); + trace2_printf("opened '%s' for writing deltas", delta_file_name); + } if (depth < 0) depth = 0; if (depth >= (1 << OE_DEPTH_BITS)) { @@ -4796,5 +4860,10 @@ cleanup: list_objects_filter_release(&filter_options); strvec_clear(&rp); + if (delta_file) { + fflush(delta_file); + fclose(delta_file); + } + return 0; } -- gitgitgadget