From: Junio C Hamano <gitster@pobox•com>
To: Nicolas Pitre <nico@fluxnic•net>
Cc: "Nguyễn Thái Ngọc Duy" <pclouds@gmail•com>, git@vger•kernel.org
Subject: Re: [PATCH v2 15/16] index-pack: use nr_objects_final as sha1_table size
Date: Mon, 09 Sep 2013 11:34:31 -0700 [thread overview]
Message-ID: <xmqq61u94zew.fsf@gitster.dls.corp.google.com> (raw)
In-Reply-To: <alpine.LFD.2.03.1309091047510.20709@syhkavp.arg> (Nicolas Pitre's message of "Mon, 09 Sep 2013 11:01:10 -0400 (EDT)")
Nicolas Pitre <nico@fluxnic•net> writes:
> On Mon, 9 Sep 2013, Nguyễn Thái Ngọc Duy wrote:
>
>> nr_objects in the next patch is used to reflect the number of actual
>> objects in the stream, which may be smaller than the number recorded
>> in pack header.
>
> This highlights an issue that has been nagging me for a while.
>
> We decided to send the final number of objects in the thin pack header
> for two reasons:
>
> 1) it allows to properly size the SHA1 table upfront which already
> contains entries for the omitted objects;
>
> 2) the whole pack doesn't have to be re-summed again after being
> completed on the receiving end since we don't alter the header.
>
> However this means that the progress meter will now be wrong and that's
> terrible ! Users *will* complain that the meter doesn't reach 100% and
> they'll protest for being denied the remaining objects during the
> transfer !
>
> Joking aside, we should think about doing something about it. I was
> wondering if some kind of prefix to the pack stream could be inserted
> onto the wire when sending a pack v4. Something like:
>
> 'T', 'H', 'I', 'N', <actual_number_of_sent_objects_in_network_order>
>
> This 8-byte prefix would simply be discarded by index-pack after being
> parsed.
>
> What do you think?
I do not think it is _too_ bad if the meter jumped from 92% to 100%
when we finish reading from the other end ;-), as long as we can
reliably tell that we read the right thing.
Which brings me to a tangent. Do we have a means to make sure that
the data received over the wire is bit-for-bit correct as a whole
when it is a thin pack stream? When it is a non-thin pack stream,
we have the checksum at the end added by sha1close() which
index-pack.c::parse_pack_objects() can (and does) verify.
next prev parent reply other threads:[~2013-09-09 18:34 UTC|newest]
Thread overview: 124+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-09-05 6:19 [PATCH 00/38] pack version 4 basic functionalities Nicolas Pitre
2013-09-05 6:19 ` [PATCH 01/38] pack v4: initial pack dictionary structure and code Nicolas Pitre
2013-09-05 6:19 ` [PATCH 02/38] export packed_object_info() Nicolas Pitre
2013-09-05 6:19 ` [PATCH 03/38] pack v4: scan tree objects Nicolas Pitre
2013-09-05 6:19 ` [PATCH 04/38] pack v4: add tree entry mode support to dictionary entries Nicolas Pitre
2013-09-05 6:19 ` [PATCH 05/38] pack v4: add commit object parsing Nicolas Pitre
2013-09-05 10:30 ` SZEDER Gábor
2013-09-05 17:30 ` Nicolas Pitre
2013-09-05 6:19 ` [PATCH 06/38] pack v4: split the object list and dictionary creation Nicolas Pitre
2013-09-05 6:19 ` [PATCH 07/38] pack v4: move to struct pack_idx_entry and get rid of our own struct idx_entry Nicolas Pitre
2013-09-05 6:19 ` [PATCH 08/38] pack v4: basic SHA1 reference encoding Nicolas Pitre
2013-09-05 6:19 ` [PATCH 09/38] introduce get_sha1_lowhex() Nicolas Pitre
2013-09-05 6:19 ` [PATCH 10/38] pack v4: commit object encoding Nicolas Pitre
2013-09-06 6:57 ` Junio C Hamano
2013-09-06 21:28 ` Nicolas Pitre
2013-09-06 22:08 ` Junio C Hamano
2013-09-07 4:41 ` Nicolas Pitre
2013-09-05 6:19 ` [PATCH 11/38] pack v4: tree " Nicolas Pitre
2013-09-05 6:19 ` [PATCH 12/38] pack v4: dictionary table output Nicolas Pitre
2013-09-05 6:19 ` [PATCH 13/38] pack v4: creation code Nicolas Pitre
2013-09-05 6:19 ` [PATCH 14/38] pack v4: object headers Nicolas Pitre
2013-09-05 6:19 ` [PATCH 15/38] pack v4: object data copy Nicolas Pitre
2013-09-05 6:19 ` [PATCH 16/38] pack v4: object writing Nicolas Pitre
2013-09-05 6:19 ` [PATCH 17/38] pack v4: tree object delta encoding Nicolas Pitre
2013-09-05 6:19 ` [PATCH 18/38] pack v4: load delta candidate for encoding tree objects Nicolas Pitre
2013-09-05 6:19 ` [PATCH 19/38] packv4-create: optimize delta encoding Nicolas Pitre
2013-09-05 6:19 ` [PATCH 20/38] pack v4: honor pack.compression config option Nicolas Pitre
2013-09-05 6:19 ` [PATCH 21/38] pack v4: relax commit parsing a bit Nicolas Pitre
2013-09-05 6:19 ` [PATCH 22/38] pack index v3 Nicolas Pitre
2013-09-05 6:19 ` [PATCH 23/38] packv4-create: normalize pack name to properly generate the pack index file name Nicolas Pitre
2013-09-05 6:19 ` [PATCH 24/38] packv4-create: add progress display Nicolas Pitre
2013-09-05 6:19 ` [PATCH 25/38] pack v4: initial pack index v3 support on the read side Nicolas Pitre
2013-09-05 6:19 ` [PATCH 26/38] pack v4: object header decode Nicolas Pitre
2013-09-05 6:19 ` [PATCH 27/38] pack v4: code to obtain a SHA1 from a sha1ref Nicolas Pitre
2013-09-05 6:19 ` [PATCH 28/38] pack v4: code to load and prepare a pack dictionary table for use Nicolas Pitre
2013-09-05 6:19 ` [PATCH 29/38] pack v4: code to retrieve a name Nicolas Pitre
2013-09-05 6:19 ` [PATCH 30/38] pack v4: code to recreate a canonical commit object Nicolas Pitre
2013-09-05 6:19 ` [PATCH 31/38] sha1_file.c: make use of decode_varint() Nicolas Pitre
2013-09-05 7:35 ` SZEDER Gábor
2013-09-05 6:19 ` [PATCH 32/38] pack v4: parse delta base reference Nicolas Pitre
2013-09-05 6:19 ` [PATCH 33/38] pack v4: we can read commit objects now Nicolas Pitre
2013-09-05 6:19 ` [PATCH 34/38] pack v4: code to retrieve a path component Nicolas Pitre
2013-09-05 6:19 ` [PATCH 35/38] pack v4: decode tree objects Nicolas Pitre
2013-09-05 6:19 ` [PATCH 36/38] pack v4: get " Nicolas Pitre
2013-09-05 6:20 ` [PATCH 37/38] pack v4: introduce "escape hatches" in the name and path indexes Nicolas Pitre
2013-09-05 19:02 ` Nicolas Pitre
2013-09-05 21:48 ` Nicolas Pitre
2013-09-05 23:57 ` Duy Nguyen
2013-09-05 6:20 ` [PATCH 38/38] packv4-create: add a command line argument to limit tree copy sequences Nicolas Pitre
2013-09-07 10:43 ` [PATCH 00/12] pack v4 support in index-pack Nguyễn Thái Ngọc Duy
2013-09-07 10:43 ` [PATCH 01/12] pack v4: split pv4_create_dict() out of load_dict() Nguyễn Thái Ngọc Duy
2013-09-07 10:43 ` [PATCH 02/12] index-pack: split out varint decoding code Nguyễn Thái Ngọc Duy
2013-09-07 10:43 ` [PATCH 03/12] index-pack: do not allocate buffer for unpacking deltas in the first pass Nguyễn Thái Ngọc Duy
2013-09-07 10:43 ` [PATCH 04/12] index-pack: split inflate/digest code out of unpack_entry_data Nguyễn Thái Ngọc Duy
2013-09-07 10:43 ` [PATCH 05/12] index-pack: parse v4 header and dictionaries Nguyễn Thái Ngọc Duy
2013-09-08 2:14 ` Nicolas Pitre
2013-09-07 10:43 ` [PATCH 06/12] index-pack: make sure all objects are registered in v4's SHA-1 table Nguyễn Thái Ngọc Duy
2013-09-07 10:43 ` [PATCH 07/12] index-pack: parse v4 commit format Nguyễn Thái Ngọc Duy
2013-09-07 10:43 ` [PATCH 08/12] index-pack: parse v4 tree format Nguyễn Thái Ngọc Duy
2013-09-08 2:52 ` Nicolas Pitre
2013-09-07 10:43 ` [PATCH 09/12] index-pack: move delta base queuing code to unpack_raw_entry Nguyễn Thái Ngọc Duy
2013-09-07 10:43 ` [PATCH 10/12] index-pack: record all delta bases in v4 (tree and ref-delta) Nguyễn Thái Ngọc Duy
2013-09-07 10:43 ` [PATCH 11/12] index-pack: skip looking for ofs-deltas in v4 as they are not allowed Nguyễn Thái Ngọc Duy
2013-09-07 10:43 ` [PATCH 12/12] index-pack: resolve v4 one-base trees Nguyễn Thái Ngọc Duy
2013-09-08 3:28 ` Nicolas Pitre
2013-09-08 3:44 ` Duy Nguyen
2013-09-08 7:22 ` [PATCH v2 00/14] pack v4 support in index-pack Nguyễn Thái Ngọc Duy
2013-09-08 7:22 ` [PATCH v2 01/14] pack v4: split pv4_create_dict() out of load_dict() Nguyễn Thái Ngọc Duy
2013-09-08 7:22 ` [PATCH v2 02/14] pack v4: add pv4_free_dict() Nguyễn Thái Ngọc Duy
2013-09-08 7:22 ` [PATCH v2 03/14] index-pack: add more comments on some big functions Nguyễn Thái Ngọc Duy
2013-09-08 7:22 ` [PATCH v2 04/14] index-pack: split out varint decoding code Nguyễn Thái Ngọc Duy
2013-09-08 7:22 ` [PATCH v2 05/14] index-pack: do not allocate buffer for unpacking deltas in the first pass Nguyễn Thái Ngọc Duy
2013-09-08 7:22 ` [PATCH v2 06/14] index-pack: split inflate/digest code out of unpack_entry_data Nguyễn Thái Ngọc Duy
2013-09-08 7:22 ` [PATCH v2 07/14] index-pack: parse v4 header and dictionaries Nguyễn Thái Ngọc Duy
2013-09-08 7:22 ` [PATCH v2 08/14] index-pack: make sure all objects are registered in v4's SHA-1 table Nguyễn Thái Ngọc Duy
2013-09-08 7:22 ` [PATCH v2 09/14] index-pack: parse v4 commit format Nguyễn Thái Ngọc Duy
2013-09-08 7:22 ` [PATCH v2 10/14] index-pack: parse v4 tree format Nguyễn Thái Ngọc Duy
2013-09-08 7:22 ` [PATCH v2 11/14] index-pack: move delta base queuing code to unpack_raw_entry Nguyễn Thái Ngọc Duy
2013-09-08 7:22 ` [PATCH v2 12/14] index-pack: record all delta bases in v4 (tree and ref-delta) Nguyễn Thái Ngọc Duy
2013-09-08 7:22 ` [PATCH v2 13/14] index-pack: skip looking for ofs-deltas in v4 as they are not allowed Nguyễn Thái Ngọc Duy
2013-09-08 7:22 ` [PATCH v2 14/14] index-pack: resolve v4 one-base trees Nguyễn Thái Ngọc Duy
2013-09-08 15:04 ` [PATCH 00/11] pack v4 support in pack-objects Nguyễn Thái Ngọc Duy
2013-09-08 15:04 ` [PATCH 01/11] pack v4: allocate dicts from the beginning Nguyễn Thái Ngọc Duy
2013-09-08 15:04 ` [PATCH 02/11] pack v4: stop using static/global variables in packv4-create.c Nguyễn Thái Ngọc Duy
2013-09-08 15:04 ` [PATCH 03/11] pack v4: move packv4-create.c to libgit.a Nguyễn Thái Ngọc Duy
2013-09-08 20:56 ` Nicolas Pitre
2013-09-08 15:04 ` [PATCH 04/11] pack v4: add version argument to write_pack_header Nguyễn Thái Ngọc Duy
2013-09-08 15:04 ` [PATCH 05/11] pack-write.c: add pv4_encode_in_pack_object_header Nguyễn Thái Ngọc Duy
2013-09-08 20:51 ` Nicolas Pitre
2013-09-08 15:04 ` [PATCH 06/11] pack-objects: add --version to specify written pack version Nguyễn Thái Ngọc Duy
2013-09-08 15:04 ` [PATCH 07/11] list-objects.c: add show_tree_entry callback to traverse_commit_list Nguyễn Thái Ngọc Duy
2013-09-08 15:04 ` [PATCH 08/11] pack-objects: create pack v4 tables Nguyễn Thái Ngọc Duy
2013-09-09 10:40 ` Duy Nguyen
2013-09-09 13:07 ` Nicolas Pitre
2013-09-09 15:21 ` Junio C Hamano
2013-09-08 15:04 ` [PATCH 09/11] pack-objects: do not cache delta for v4 trees Nguyễn Thái Ngọc Duy
2013-09-08 15:04 ` [PATCH 10/11] pack-objects: exclude commits out of delta objects in v4 Nguyễn Thái Ngọc Duy
2013-09-08 15:04 ` [PATCH 11/11] pack-objects: support writing pack v4 Nguyễn Thái Ngọc Duy
2013-09-09 13:57 ` [PATCH v2 00/16] pack v4 support in pack-objects Nguyễn Thái Ngọc Duy
2013-09-09 13:57 ` [PATCH v2 01/16] pack v4: allocate dicts from the beginning Nguyễn Thái Ngọc Duy
2013-09-09 13:57 ` [PATCH v2 02/16] pack v4: stop using static/global variables in packv4-create.c Nguyễn Thái Ngọc Duy
2013-09-09 13:57 ` [PATCH v2 03/16] pack v4: move packv4-create.c to libgit.a Nguyễn Thái Ngọc Duy
2013-09-09 13:57 ` [PATCH v2 04/16] pack v4: add version argument to write_pack_header Nguyễn Thái Ngọc Duy
2013-09-09 13:57 ` [PATCH v2 05/16] pack_write: tighten valid object type check in encode_in_pack_object_header Nguyễn Thái Ngọc Duy
2013-09-09 13:57 ` [PATCH v2 06/16] pack-write.c: add pv4_encode_object_header Nguyễn Thái Ngọc Duy
2013-09-09 13:57 ` [PATCH v2 07/16] pack-objects: add --version to specify written pack version Nguyễn Thái Ngọc Duy
2013-09-09 13:57 ` [PATCH v2 08/16] list-objects.c: add show_tree_entry callback to traverse_commit_list Nguyễn Thái Ngọc Duy
2013-09-09 13:58 ` [PATCH v2 09/16] pack-objects: do not cache delta for v4 trees Nguyễn Thái Ngọc Duy
2013-09-09 13:58 ` [PATCH v2 10/16] pack-objects: exclude commits out of delta objects in v4 Nguyễn Thái Ngọc Duy
2013-09-09 13:58 ` [PATCH v2 11/16] pack-objects: create pack v4 tables Nguyễn Thái Ngọc Duy
2013-09-09 13:58 ` [PATCH v2 12/16] pack-objects: prepare SHA-1 table in v4 Nguyễn Thái Ngọc Duy
2013-09-09 13:58 ` [PATCH v2 13/16] pack-objects: support writing pack v4 Nguyễn Thái Ngọc Duy
2013-09-09 13:58 ` [PATCH v2 14/16] pack v4: support "end-of-pack" indicator in index-pack and pack-objects Nguyễn Thái Ngọc Duy
2013-09-09 13:58 ` [PATCH v2 15/16] index-pack: use nr_objects_final as sha1_table size Nguyễn Thái Ngọc Duy
2013-09-09 15:01 ` Nicolas Pitre
2013-09-09 18:34 ` Junio C Hamano [this message]
2013-09-09 18:46 ` Nicolas Pitre
2013-09-09 18:56 ` Junio C Hamano
2013-09-09 19:11 ` Nicolas Pitre
2013-09-09 19:30 ` Junio C Hamano
2013-09-09 19:56 ` Nicolas Pitre
2013-09-10 0:45 ` Duy Nguyen
2013-09-12 15:34 ` Nicolas Pitre
2013-09-09 13:58 ` [PATCH v2 16/16] index-pack: support completing thin packs v4 Nguyễn Thái Ngọc Duy
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