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2011-03-11doc: drop author/documentation sections from most pagesLibravatar Jeff King1-9/+0
The point of these sections is generally to: 1. Give credit where it is due. 2. Give the reader an idea of where to ask questions or file bug reports. But they don't do a good job of either case. For (1), they are out of date and incomplete. A much more accurate answer can be gotten through shortlog or blame. For (2), the correct contact point is generally git@vger, and even if you wanted to cc the contact point, the out-of-date and incomplete fields mean you're likely sending to somebody useless. So let's drop the fields entirely from all manpages except git(1) itself. We already point people to the mailing list for bug reports there, and we can update the Authors section to give credit to the major contributors and point to shortlog and blame for more information. Each page has a "This is part of git" footer, so people can follow that to the main git manpage.
2010-10-08Use parentheses and `...' where appropriateLibravatar Štěpán Němec1-1/+1
Remove some stray usage of other bracket types and asterisks for the same purpose. Signed-off-by: Štěpán Němec <stepnem@gmail.com> Acked-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-10-08Use angles for placeholders consistentlyLibravatar Štěpán Němec1-7/+7
Signed-off-by: Štěpán Němec <stepnem@gmail.com> Acked-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-02-24pack-objects documentation: Fix --honor-pack-keep as well.Libravatar Nelson Elhage1-2/+2
Signed-off-by: Nelson Elhage <nelhage@mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-02-24pack-objects documentation: reword "objects that appear in the standard input"Libravatar Junio C Hamano1-3/+3
These were written back when we always read objects from the standard input. These days --revs and its friends can feed only the start and end points and have the command internally enumerate the objects. Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-02-20Documentation: pack-objects: Clarify --local's semantics.Libravatar Nelson Elhage1-5/+4
The current documentation suggests that --local also ignores any objects in local packs, which is incorrect. Change the language to be clearer and more parallel to the other options that ignore objects. While we're at it, fix a trivial error in --incremental's documentation. Signed-off-by: Nelson Elhage <nelhage@mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-02-18Documentation: describe --thin more accuratelyLibravatar Stephen Boyd1-13/+24
The description for --thin was misleading and downright wrong. Correct it with some inspiration from the description of index-pack's --fix-thin and some background information from Nicolas Pitre <nico@fluxnic.net>. Signed-off-by: Stephen Boyd <bebarino@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-02-17docs: don't talk about $GIT_DIR/refs/ everywhereLibravatar Jeff King1-1/+1
It is misleading to say that we pull refs from $GIT_DIR/refs/*, because we may also consult the packed refs mechanism. These days we tend to treat the "refs hierarchy" as more of an abstract namespace that happens to be represented as $GIT_DIR/refs. At best, this is a minor inaccuracy, but at worst it can confuse users who then look in $GIT_DIR/refs and find that it is missing some of the refs they expected to see. This patch drops most uses of "$GIT_DIR/refs/*", changing them into just "refs/*", under the assumption that users can handle the concept of an abstract refs namespace. There are a few things to note: - most cases just dropped the $GIT_DIR/ portion. But for cases where that left _just_ the word "refs", I changed it to "refs/" to help indicate that it was a hierarchy. I didn't do the same for longer paths (e.g., "refs/heads" remained, instead of becoming "refs/heads/"). - in some cases, no change was made, as the text was explicitly about unpacked refs (e.g., the discussion in git-pack-refs). - In some cases it made sense instead to note the existence of packed refs (e.g., in check-ref-format and rev-parse). Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-02-03make --max-pack-size argument to 'git pack-object' count in bytesLibravatar Nicolas Pitre1-2/+3
The value passed to --max-pack-size used to count in MiB which was inconsistent with the corresponding configuration variable as well as other command arguments which are defined to count in bytes with an optional unit suffix. This brings --max-pack-size in line with the rest of Git. Also, in order not to cause havoc with people used to the previous megabyte scale, and because this is a sane thing to do anyway, a minimum size of 1 MiB is enforced to avoid an explosion of pack files. Adjust and extend test suite accordingly. Signed-off-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-01-10Documentation: spell 'git cmd' without dash throughoutLibravatar Thomas Rast1-3/+3
The documentation was quite inconsistent when spelling 'git cmd' if it only refers to the program, not to some specific invocation syntax: both 'git-cmd' and 'git cmd' spellings exist. The current trend goes towards dashless forms, and there is precedent in 647ac70 (git-svn.txt: stop using dash-form of commands., 2009-07-07) to actively eliminate the dashed variants. Replace 'git-cmd' with 'git cmd' throughout, except where git-shell, git-cvsserver, git-upload-pack, git-receive-pack, and git-upload-archive are concerned, because those really live in the $PATH.
2009-11-23pack-objects: split implications of --all-progress from progress activationLibravatar Nicolas Pitre1-3/+9
Currently the --all-progress flag is used to use force progress display during the writing object phase even if output goes to stdout which is primarily the case during a push operation. This has the unfortunate side effect of forcing progress display even if stderr is not a terminal. Let's introduce the --all-progress-implied argument which has the same intent except for actually forcing the activation of any progress display. With this, progress display will be automatically inhibited whenever stderr is not a terminal, or full progress display will be included otherwise. This should let people use 'git push' within a cron job without filling their logs with useless percentage displays. Signed-off-by: Nicolas Pitre <nico@fluxnic.net> Tested-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-07-24git repack: keep commits hidden by a graftLibravatar Johannes Schindelin1-1/+6
When you have grafts that pretend that a given commit has different parents than the ones recorded in the commit object, it is dangerous to let 'git repack' remove those hidden parents, as you can easily remove the graft and end up with a broken repository. So let's play it safe and keep those parent objects and everything that is reachable by them, in addition to the grafted parents. As this behavior can only be triggered by git pack-objects, and as that command handles duplicate parents gracefully, we do not bother to cull duplicated parents that may result by using both true and grafted parents. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-11-12pack-objects: extend --local to mean ignore non-local loose objects tooLibravatar Brandon Casey1-1/+1
With this patch, --local means pack only local objects that are not already packed. Additionally, this fixes t7700 testing whether loose objects in an alternate object database are repacked. Signed-off-by: Brandon Casey <drafnel@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-11-12pack-objects: new option --honor-pack-keepLibravatar Brandon Casey1-0/+5
This adds a new option to pack-objects which will cause it to ignore an object which appears in a local pack which has a .keep file, even if it was specified for packing. This option will be used by the porcelain repack. Signed-off-by: Brandon Casey <casey@nrlssc.navy.mil> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-07-05manpages: italicize git command names (which were in teletype font)Libravatar Jonathan Nieder1-3/+3
The names of git commands are not meant to be entered at the commandline; they are just names. So we render them in italics, as is usual for command names in manpages. Using doit () { perl -e 'for (<>) { s/\`(git-[^\`.]*)\`/'\''\1'\''/g; print }' } for i in git*.txt config.txt diff*.txt blame*.txt fetch*.txt i18n.txt \ merge*.txt pretty*.txt pull*.txt rev*.txt urls*.txt do doit <"$i" >"$i+" && mv "$i+" "$i" done git diff . Signed-off-by: Jonathan Nieder <jrnieder@uchicago.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-07-01Documentation formatting and cleanupLibravatar Jonathan Nieder1-4/+4
Following what appears to be the predominant style, format names of commands and commandlines both as `teletype text`. While we're at it, add articles ("a" and "the") in some places, italicize the name of the command in the manual page synopsis line, and add a comma or two where it seems appropriate. Signed-off-by: Jonathan Nieder <jrnieder@uchicago.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-07-01Documentation: be consistent about "git-" versus "git "Libravatar Jonathan Nieder1-1/+1
Since the git-* commands are not installed in $(bindir), using "git-command <parameters>" in examples in the documentation is not a good idea. On the other hand, it is nice to be able to refer to each command using one hyphenated word. (There is no escaping it, anyway: man page names cannot have spaces in them.) This patch retains the dash in naming an operation, command, program, process, or action. Complete command lines that can be entered at a shell (i.e., without options omitted) are made to use the dashless form. The changes consist only of replacing some spaces with hyphens and vice versa. After a "s/ /-/g", the unpatched and patched versions are identical. Signed-off-by: Jonathan Nieder <jrnieder@uchicago.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-06-08Docs: Use "-l::\n--long\n" format in OPTIONS sectionsLibravatar Stephan Beyer1-1/+2
The OPTIONS section of a documentation file contains a list of the options a git command accepts. Currently there are several variants to describe the case that different options (almost) do the same in the OPTIONS section. Some are: -f, --foo:: -f|--foo:: -f | --foo:: But AsciiDoc has the special form: -f:: --foo:: This patch applies this form to the documentation of the whole git suite, and removes useless em-dash prevention, so \--foo becomes --foo. Signed-off-by: Stephan Beyer <s-beyer@gmx.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-06-06documentation: move git(7) to git(1)Libravatar Christian Couder1-1/+1
As the "git" man page describes the "git" command at the end-user level, it seems better to move it to man section 1. Signed-off-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-05-28Manual subsection to refer to other pages is SEE ALSOLibravatar Junio C Hamano1-1/+1
Consistently say so in all caps as it is customary to do so. Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-04-05git-pack-objects.txt: Make wording slightly less ambiguousLibravatar Peter Eriksen1-2/+3
It is a bit confusing on first read, that "The packed archive format (.pack) is designed to be unpackable..." Signed-off-by: Peter Eriksen <s022018@student.dtu.dk> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-03-04git-pack-objects: Automatically pack annotated tags if object was packedLibravatar Shawn O. Pearce1-0/+5
The new option "--include-tag" allows the caller to request that any annotated tag be included into the packfile if the object the tag references was also included as part of the packfile. This option can be useful on the server side of a native git transport, where the server knows what commits it is including into a packfile to update the client. If new annotated tags have been introduced then we can also include them in the packfile, saving the client from needing to request them through a second connection. This change only introduces the backend option and provides a test. Protocol extensions to make this useful in fetch-pack/upload-pack are still necessary to activate the logic during transport. Signed-off-by: Shawn O. Pearce <spearce@spearce.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-02-23pack-objects: Add runtime detection of online CPU'sLibravatar Andreas Ericsson1-0/+2
Packing objects can be done in parallell nowadays, but it's only done if the config option pack.threads is set to a value above 1. Because of that, the code-path used is often not the most optimal one. This patch adds a routine to detect the number of online CPU's at runtime (online_cpus()). When pack.threads (or --threads=) is given a value of 0, the number of threads is set to the number of online CPU's. This feature is also documented. As per Nicolas Pitre's recommendations, the default is still to run pack-objects single-threaded unless explicitly activated, either by configuration or by command line parameter. The routine online_cpus() is a rework of "numcpus.c", written by one Philip Willoughby <pgw99@doc.ic.ac.uk>. numcpus.c is in the public domain and can presently be downloaded from http://csgsoft.doc.ic.ac.uk/numcpus/ Signed-off-by: Andreas Ericsson <ae@op5.se> Signed-off-by: Brandon Casey <casey@nrlssc.navy.mil> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-02-09Introduce the config variable pack.packSizeLimitLibravatar Johannes Schindelin1-1/+2
"git pack-objects" has the option --max-pack-size to limit the file size of the packs to a certain amount of bytes. On platforms where the pack file size is limited by filesystem constraints, it is easy to forget this option, and this option does not exist for "git gc" to begin with. So introduce a config variable to set the default maximum, but make this overrideable by the command line. Suggested by Tor Arvid Lund. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-01-06Documentation: rename gitlink macro to linkgitLibravatar Dan McGee1-5/+5
Between AsciiDoc 8.2.2 and 8.2.3, the following change was made to the stock Asciidoc configuration: @@ -149,7 +153,10 @@ # Inline macros. # Backslash prefix required for escape processing. # (?s) re flag for line spanning. -(?su)[\\]?(?P<name>\w(\w|-)*?):(?P<target>\S*?)(\[(?P<attrlist>.*?)\])= + +# Explicit so they can be nested. +(?su)[\\]?(?P<name>(http|https|ftp|file|mailto|callto|image|link)):(?P<target>\S*?)(\[(?P<attrlist>.*?)\])= + # Anchor: [[[id]]]. Bibliographic anchor. (?su)[\\]?\[\[\[(?P<attrlist>[\w][\w-]*?)\]\]\]=anchor3 # Anchor: [[id,xreflabel]] This default regex now matches explicit values, and unfortunately in this case gitlink was being matched by just 'link', causing the wrong inline macro template to be applied. By renaming the macro, we can avoid being matched by the wrong regex. Signed-off-by: Dan McGee <dpmcgee@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-09-23Merge branch 'maint'Libravatar Junio C Hamano1-4/+4
* maint: git-svn: don't attempt to spawn pager if we don't want one Supplant the "while case ... break ;; esac" idiom User Manual: add a chapter for submodules user-manual: don't assume refs are stored under .git/refs Detect exec bit in more cases. Conjugate "search" correctly in the git-prune-packed man page. Move the paragraph specifying where the .idx and .pack files should be Documentation/git-lost-found.txt: drop unnecessarily duplicated name.
2007-09-21Move the paragraph specifying where the .idx and .pack files should beLibravatar Matt Kraai1-4/+4
Signed-off-by: Matt Kraai <kraai@ftbfs.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-09-14Merge branch 'np/delta'Libravatar Junio C Hamano1-0/+8
* np/delta: builtin-pack-objects.c: avoid bogus gcc warnings threaded delta search: proper locking for cache accounting threaded delta search: add pack.threads config variable fix threaded delta search locking threaded delta search: specify number of threads at run time threaded delta search: better chunck split point threaded delta search: refine work allocation basic threaded delta search rearrange delta search progress reporting localize window memory usage accounting straighten the list of objects to deltify
2007-09-09fix doc for --compression argument to pack-objectsLibravatar Nicolas Pitre1-6/+2
Remove obsolete details (core.legacyheaders is always true now). Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-09-09threaded delta search: specify number of threads at run timeLibravatar Nicolas Pitre1-0/+8
This adds a --threads=<n> parameter to 'git pack-objects' with documentation. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-07-12Add documentation for --window-memory, pack.windowMemoryLibravatar Brian Downing1-0/+11
Signed-off-by: Brian Downing <bdowning@lavos.net> Acked-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-06-07War on whitespaceLibravatar Junio C Hamano1-1/+0
This uses "git-apply --whitespace=strip" to fix whitespace errors that have crept in to our source files over time. There are a few files that need to have trailing whitespaces (most notably, test vectors). The results still passes the test, and build result in Documentation/ area is unchanged. Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-05-20git-repack --max-pack-size: add option parsing to enable featureLibravatar Dana L. How1-0/+5
Add --max-pack-size parsing and usage messages. Upgrade git-repack.sh to handle multiple packfile names, and build packfiles in GIT_OBJECT_DIRECTORY not GIT_DIR. Update documentation. Signed-off-by: Dana L. How <danahow@gmail.com> Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-05-10Custom compression levels for objects and packsLibravatar Dana How1-1/+13
Add config variables pack.compression and core.loosecompression , and switch --compression=level to pack-objects. Loose objects will be compressed using core.loosecompression if set, else core.compression if set, else Z_BEST_SPEED. Packed objects will be compressed using --compression=level if seen, else pack.compression if set, else core.compression if set, else Z_DEFAULT_COMPRESSION. This is the "pack compression level". Loose objects added to a pack undeltified will be recompressed to the pack compression level if it is unequal to the current loose compression level by the preceding rules, or if the loose object was written while core.legacyheaders = true. Newly deltified loose objects are always compressed to the current pack compression level. Previously packed objects added to a pack are recompressed to the current pack compression level exactly when their deltification status changes, since the previous pack data cannot be reused. In either case, the --no-reuse-object switch from the first patch below will always force recompression to the current pack compression level, instead of assuming the pack compression level hasn't changed and pack data can be reused when possible. This applies on top of the following patches from Nicolas Pitre: [PATCH] allow for undeltified objects not to be reused [PATCH] make "repack -f" imply "pack-objects --no-reuse-object" Signed-off-by: Dana L. How <danahow@gmail.com> Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-05-10allow for undeltified objects not to be reusedLibravatar Nicolas Pitre1-0/+7
Currently non deltified object data is always reused when possible. This means that any change to core.compression has no effect on those objects as they don't get recompressed when repacking them. Let's add a --no-reuse-object flag to git-repack in order to force recompression of all objects when desired. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-05-08Increase pack.depth default to 50Libravatar Theodore Ts'o1-1/+1
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-05-08Add pack.depth option to git-pack-objects.Libravatar Theodore Ts'o1-1/+1
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-04-19document --index-version for index-pack and pack-objectsLibravatar Nicolas Pitre1-0/+5
Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <junkio@cox.net>
2006-11-07git-pack-objects progress flag documentation and cleanupLibravatar Nicolas Pitre1-0/+17
This adds documentation for --progress and --all-progress, remove a duplicate --progress handling and make usage string more readable. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <junkio@cox.net>
2006-11-01make git-push a bit more verboseLibravatar Nicolas Pitre1-1/+1
Currently git-push displays progress status for the local packing of objects to send, but nothing once it starts to push it over the connection. Having progress status in that later case is especially nice when pushing lots of objects over a slow network link. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <junkio@cox.net>
2006-11-01Merge branch 'maint'Libravatar Junio C Hamano1-3/+2
* maint: pack-objects doesn't create random pack names link_temp_to_file: don't leave the path truncated on adjust_shared_perm failure
2006-11-01pack-objects doesn't create random pack namesLibravatar Nicolas Pitre1-3/+2
Documentation for pack-objects seems to be out of date in this regard. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <junkio@cox.net>
2006-10-22Merge branch 'np/pack'Libravatar Junio C Hamano1-1/+12
* np/pack: add the capability for index-pack to read from a stream index-pack: compare only the first 20-bytes of the key. git-repack: repo.usedeltabaseoffset pack-objects: document --delta-base-offset option allow delta data reuse even if base object is a preferred base zap a debug remnant let the GIT native protocol use offsets to delta base when possible make pack data reuse compatible with both delta types make git-pack-objects able to create deltas with offset to base teach git-index-pack about deltas with offset to base teach git-unpack-objects about deltas with offset to base introduce delta objects with offset to base
2006-10-10pack-objects: document --delta-base-offset optionLibravatar Junio C Hamano1-1/+12
Signed-off-by: Junio C Hamano <junkio@cox.net>
2006-10-06Add default values for --window and --depth to the docsLibravatar Dennis Stosberg1-3/+4
Currently, you actually have to read the source to find out the default values. While at it, fix two typos and suggest that these options actually take a parameter in git-pack-objects.txt. Signed-off-by: Dennis Stosberg <dennis@stosberg.net> Signed-off-by: Junio C Hamano <junkio@cox.net>
2006-09-12pack-objects: document --revs, --unpacked and --all.Libravatar Junio C Hamano1-1/+20
Signed-off-by: Junio C Hamano <junkio@cox.net>
2006-03-09Remove trailing dot after short descriptionLibravatar Fredrik Kuivinen1-1/+1
Signed-off-by: Fredrik Kuivinen <freku045@student.liu.se> Signed-off-by: Junio C Hamano <junkio@cox.net>
2006-03-05cosmetics: change from 'See-Also' to 'See Also'Libravatar Jeff Muizelaar1-1/+1
Changes the documentation that uses 'See-Also' to the more common 'See Also' form. Signed-off-by: Junio C Hamano <junkio@cox.net>
2006-02-17pack-objects: finishing touches.Libravatar Junio C Hamano1-1/+20
This introduces --no-reuse-delta option to disable reusing of existing delta, which is a large part of the optimization introduced by this series. This may become necessary if repeated repacking makes delta chain too long. With this, the output of the command becomes identical to that of the older implementation. But the performance suffers greatly. It still allows reusing non-deltified representations; there is no point uncompressing and recompressing the whole text. It also adds a couple more statistics output, while squelching it under -q flag, which the last round forgot to do. $ time old-git-pack-objects --stdout >/dev/null <RL Generating pack... Done counting 184141 objects. Packing 184141 objects.................... real 12m8.530s user 11m1.450s sys 0m57.920s $ time git-pack-objects --stdout >/dev/null <RL Generating pack... Done counting 184141 objects. Packing 184141 objects..................... Total 184141, written 184141 (delta 138297), reused 178833 (delta 134081) real 0m59.549s user 0m56.670s sys 0m2.400s $ time git-pack-objects --stdout --no-reuse-delta >/dev/null <RL Generating pack... Done counting 184141 objects. Packing 184141 objects..................... Total 184141, written 184141 (delta 134833), reused 47904 (delta 0) real 11m13.830s user 9m45.240s sys 0m44.330s There is one remaining issue when --no-reuse-delta option is not used. It can create delta chains that are deeper than specified. A<--B<--C<--D E F G Suppose we have a delta chain A to D (A is stored in full either in a pack or as a loose object. B is depth1 delta relative to A, C is depth2 delta relative to B...) with loose objects E, F, G. And we are going to pack all of them. B, C and D are left as delta against A, B and C respectively. So A, E, F, and G are examined for deltification, and let's say we decided to keep E expanded, and store the rest as deltas like this: E<--F<--G<--A Oops. We ended up making D a bit too deep, didn't we? B, C and D form a chain on top of A! This is because we did not know what the final depth of A would be, when we checked objects and decided to keep the existing delta. Unfortunately, deferring the decision until just before the deltification is not an option. To be able to make B, C, and D candidates for deltification with the rest, we need to know the type and final unexpanded size of them, but the major part of the optimization comes from the fact that we do not read the delta data to do so -- getting the final size is quite an expensive operation. To prevent this from happening, we should keep A from being deltified. But how would we tell that, cheaply? To do this most precisely, after check_object() runs, each object that is used as the base object of some existing delta needs to be marked with the maximum depth of the objects we decided to keep deltified (in this case, D is depth 3 relative to A, so if no other delta chain that is longer than 3 based on A exists, mark A with 3). Then when attempting to deltify A, we would take that number into account to see if the final delta chain that leads to D becomes too deep. However, this is a bit cumbersome to compute, so we would cheat and reduce the maximum depth for A arbitrarily to depth/4 in this implementation. Signed-off-by: Junio C Hamano <junkio@cox.net>
2005-12-29Documentation: spell.Libravatar Junio C Hamano1-1/+1
Signed-off-by: Junio C Hamano <junkio@cox.net>