зеркало из https://github.com/microsoft/git.git
Correct spelling of fast-import in docs.
Its spelled 'fast-import', not 'gfi'. Linus and Dscho have both recently pointed this out to me on the mailing list. Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
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@ -15,15 +15,15 @@ DESCRIPTION
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This program is usually not what the end user wants to run directly.
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Most end users want to use one of the existing frontend programs,
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which parses a specific type of foreign source and feeds the contents
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stored there to git-fast-import (gfi).
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stored there to git-fast-import.
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gfi reads a mixed command/data stream from standard input and
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fast-import reads a mixed command/data stream from standard input and
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writes one or more packfiles directly into the current repository.
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When EOF is received on standard input, fast import writes out
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updated branch and tag refs, fully updating the current repository
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with the newly imported data.
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The gfi backend itself can import into an empty repository (one that
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The fast-import backend itself can import into an empty repository (one that
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has already been initialized by gitlink:git-init[1]) or incrementally
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update an existing populated repository. Whether or not incremental
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imports are supported from a particular foreign source depends on
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@ -34,7 +34,7 @@ OPTIONS
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-------
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--date-format=<fmt>::
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Specify the type of dates the frontend will supply to
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gfi within `author`, `committer` and `tagger` commands.
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fast-import within `author`, `committer` and `tagger` commands.
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See ``Date Formats'' below for details about which formats
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are supported, and their syntax.
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@ -65,28 +65,28 @@ OPTIONS
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have been completed.
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--quiet::
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Disable all non-fatal output, making gfi silent when it
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Disable all non-fatal output, making fast-import silent when it
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is successful. This option disables the output shown by
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\--stats.
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--stats::
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Display some basic statistics about the objects gfi has
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Display some basic statistics about the objects fast-import has
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created, the packfiles they were stored into, and the
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memory used by gfi during this run. Showing this output
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memory used by fast-import during this run. Showing this output
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is currently the default, but can be disabled with \--quiet.
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Performance
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-----------
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The design of gfi allows it to import large projects in a minimum
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The design of fast-import allows it to import large projects in a minimum
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amount of memory usage and processing time. Assuming the frontend
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is able to keep up with gfi and feed it a constant stream of data,
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is able to keep up with fast-import and feed it a constant stream of data,
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import times for projects holding 10+ years of history and containing
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100,000+ individual commits are generally completed in just 1-2
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hours on quite modest (~$2,000 USD) hardware.
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Most bottlenecks appear to be in foreign source data access (the
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source just cannot extract revisions fast enough) or disk IO (gfi
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source just cannot extract revisions fast enough) or disk IO (fast-import
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writes as fast as the disk will take the data). Imports will run
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faster if the source data is stored on a different drive than the
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destination Git repository (due to less IO contention).
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@ -94,28 +94,28 @@ destination Git repository (due to less IO contention).
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Development Cost
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----------------
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A typical frontend for gfi tends to weigh in at approximately 200
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A typical frontend for fast-import tends to weigh in at approximately 200
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lines of Perl/Python/Ruby code. Most developers have been able to
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create working importers in just a couple of hours, even though it
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is their first exposure to gfi, and sometimes even to Git. This is
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is their first exposure to fast-import, and sometimes even to Git. This is
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an ideal situation, given that most conversion tools are throw-away
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(use once, and never look back).
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Parallel Operation
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------------------
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Like `git-push` or `git-fetch`, imports handled by gfi are safe to
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Like `git-push` or `git-fetch`, imports handled by fast-import are safe to
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run alongside parallel `git repack -a -d` or `git gc` invocations,
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or any other Git operation (including `git prune`, as loose objects
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are never used by gfi).
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are never used by fast-import).
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gfi does not lock the branch or tag refs it is actively importing.
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After the import, during its ref update phase, gfi tests each
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fast-import does not lock the branch or tag refs it is actively importing.
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After the import, during its ref update phase, fast-import tests each
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existing branch ref to verify the update will be a fast-forward
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update (the commit stored in the ref is contained in the new
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history of the commit to be written). If the update is not a
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fast-forward update, gfi will skip updating that ref and instead
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prints a warning message. gfi will always attempt to update all
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fast-forward update, fast-import will skip updating that ref and instead
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prints a warning message. fast-import will always attempt to update all
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branch refs, and does not stop on the first failure.
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Branch updates can be forced with \--force, but its recommended that
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@ -125,35 +125,35 @@ is not necessary for an initial import into an empty repository.
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Technical Discussion
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--------------------
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gfi tracks a set of branches in memory. Any branch can be created
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fast-import tracks a set of branches in memory. Any branch can be created
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or modified at any point during the import process by sending a
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`commit` command on the input stream. This design allows a frontend
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program to process an unlimited number of branches simultaneously,
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generating commits in the order they are available from the source
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data. It also simplifies the frontend programs considerably.
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gfi does not use or alter the current working directory, or any
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fast-import does not use or alter the current working directory, or any
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file within it. (It does however update the current Git repository,
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as referenced by `GIT_DIR`.) Therefore an import frontend may use
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the working directory for its own purposes, such as extracting file
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revisions from the foreign source. This ignorance of the working
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directory also allows gfi to run very quickly, as it does not
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directory also allows fast-import to run very quickly, as it does not
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need to perform any costly file update operations when switching
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between branches.
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Input Format
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------------
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With the exception of raw file data (which Git does not interpret)
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the gfi input format is text (ASCII) based. This text based
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the fast-import input format is text (ASCII) based. This text based
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format simplifies development and debugging of frontend programs,
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especially when a higher level language such as Perl, Python or
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Ruby is being used.
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gfi is very strict about its input. Where we say SP below we mean
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fast-import is very strict about its input. Where we say SP below we mean
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*exactly* one space. Likewise LF means one (and only one) linefeed.
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Supplying additional whitespace characters will cause unexpected
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results, such as branch names or file names with leading or trailing
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spaces in their name, or early termination of gfi when it encounters
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spaces in their name, or early termination of fast-import when it encounters
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unexpected input.
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Date Formats
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@ -164,7 +164,7 @@ in the \--date-format=<fmt> command line option.
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`raw`::
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This is the Git native format and is `<time> SP <offutc>`.
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It is also gfi's default format, if \--date-format was
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It is also fast-import's default format, if \--date-format was
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not specified.
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+
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The time of the event is specified by `<time>` as the number of
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@ -184,7 +184,7 @@ by users who are located in the same location and timezone. In this
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case a reasonable offset from UTC could be assumed.
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+
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Unlike the `rfc2822` format, this format is very strict. Any
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variation in formatting will cause gfi to reject the value.
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variation in formatting will cause fast-import to reject the value.
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`rfc2822`::
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This is the standard email format as described by RFC 2822.
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@ -206,7 +206,7 @@ value to UTC prior to storage. Therefore it is important that
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this information be as accurate as possible.
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+
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If the source material uses RFC 2822 style dates,
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the frontend should let gfi handle the parsing and conversion
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the frontend should let fast-import handle the parsing and conversion
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(rather than attempting to do it itself) as the Git parser has
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been well tested in the wild.
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+
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@ -221,7 +221,7 @@ ambiguity in parsing.
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+
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This is a toy format. The current time and timezone of this system
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is always copied into the identity string at the time it is being
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created by gfi. There is no way to specify a different time or
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created by fast-import. There is no way to specify a different time or
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timezone.
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+
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This particular format is supplied as its short to implement and
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@ -238,7 +238,7 @@ date format other than `now`.
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Commands
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~~~~~~~~
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gfi accepts several commands to update the current repository
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fast-import accepts several commands to update the current repository
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and control the current import process. More detailed discussion
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(with examples) of each command follows later.
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@ -264,7 +264,7 @@ and control the current import process. More detailed discussion
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needed to perform an import.
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`checkpoint`::
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Forces gfi to close the current packfile, generate its
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Forces fast-import to close the current packfile, generate its
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unique SHA-1 checksum and index, and start a new packfile.
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This command is optional and is not needed to perform
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an import.
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@ -293,7 +293,7 @@ Git, so importing the CVS branch symbol `RELENG-1_0` would use
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`<ref>` must be a valid refname in Git. As `LF` is not valid in
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a Git refname, no quoting or escaping syntax is supported here.
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A `mark` command may optionally appear, requesting gfi to save a
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A `mark` command may optionally appear, requesting fast-import to save a
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reference to the newly created commit for future use by the frontend
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(see below for format). It is very common for frontends to mark
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every commit they create, thereby allowing future branch creation
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@ -303,7 +303,7 @@ The `data` command following `committer` must supply the commit
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message (see below for `data` command syntax). To import an empty
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commit message use a 0 length data. Commit messages are free-form
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and are not interpreted by Git. Currently they must be encoded in
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UTF-8, as gfi does not permit other encodings to be specified.
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UTF-8, as fast-import does not permit other encodings to be specified.
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Zero or more `filemodify`, `filedelete` and `filedeleteall` commands
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may be included to update the contents of the branch prior to
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@ -316,7 +316,7 @@ wipes the branch clean (see below).
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^^^^^^^^
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An `author` command may optionally appear, if the author information
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might differ from the committer information. If `author` is omitted
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then gfi will automatically use the committer's information for
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then fast-import will automatically use the committer's information for
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the author portion of the commit. See below for a description of
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the fields in `author`, as they are identical to `committer`.
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@ -341,12 +341,12 @@ their syntax.
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`from`
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^^^^^^
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Only valid for the first commit made on this branch by this
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gfi process. The `from` command is used to specify the commit
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fast-import process. The `from` command is used to specify the commit
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to initialize this branch from. This revision will be the first
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ancestor of the new commit.
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Omitting the `from` command in the first commit of a new branch will
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cause gfi to create that commit with no ancestor. This tends to be
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cause fast-import to create that commit with no ancestor. This tends to be
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desired only for the initial commit of a project. Omitting the
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`from` command on existing branches is required, as the current
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commit on that branch is automatically assumed to be the first
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@ -357,13 +357,13 @@ quoting or escaping syntax is supported within `<committish>`.
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Here `<committish>` is any of the following:
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* The name of an existing branch already in gfi's internal branch
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table. If gfi doesn't know the name, its treated as a SHA-1
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* The name of an existing branch already in fast-import's internal branch
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table. If fast-import doesn't know the name, its treated as a SHA-1
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expression.
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* A mark reference, `:<idnum>`, where `<idnum>` is the mark number.
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+
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The reason gfi uses `:` to denote a mark reference is this character
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The reason fast-import uses `:` to denote a mark reference is this character
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is not legal in a Git branch name. The leading `:` makes it easy
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to distingush between the mark 42 (`:42`) and the branch 42 (`42`
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or `refs/heads/42`), or an abbreviated SHA-1 which happened to
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@ -381,10 +381,10 @@ current branch value should be written as:
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----
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from refs/heads/branch^0
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----
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The `{caret}0` suffix is necessary as gfi does not permit a branch to
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The `{caret}0` suffix is necessary as fast-import does not permit a branch to
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start from itself, and the branch is created in memory before the
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`from` command is even read from the input. Adding `{caret}0` will force
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gfi to resolve the commit through Git's revision parsing library,
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fast-import to resolve the commit through Git's revision parsing library,
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rather than its internal branch table, thereby loading in the
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existing value of the branch.
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|
@ -392,7 +392,7 @@ existing value of the branch.
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^^^^^^^
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Includes one additional ancestor commit, and makes the current
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commit a merge commit. An unlimited number of `merge` commands per
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commit are permitted by gfi, thereby establishing an n-way merge.
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commit are permitted by fast-import, thereby establishing an n-way merge.
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However Git's other tools never create commits with more than 15
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additional ancestors (forming a 16-way merge). For this reason
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it is suggested that frontends do not use more than 15 `merge`
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|
@ -493,14 +493,14 @@ update the content.
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Issuing a `filedeleteall` followed by the needed `filemodify`
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commands to set the correct content will produce the same results
|
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as sending only the needed `filemodify` and `filedelete` commands.
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The `filedeleteall` approach may however require gfi to use slightly
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The `filedeleteall` approach may however require fast-import to use slightly
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more memory per active branch (less than 1 MiB for even most large
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projects); so frontends that can easily obtain only the affected
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paths for a commit are encouraged to do so.
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`mark`
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~~~~~~
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Arranges for gfi to save a reference to the current object, allowing
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Arranges for fast-import to save a reference to the current object, allowing
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the frontend to recall this object at a future point in time, without
|
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knowing its SHA-1. Here the current object is the object creation
|
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command the `mark` command appears within. This can be `commit`,
|
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|
@ -536,7 +536,7 @@ where `<name>` is the name of the tag to create.
|
|||
|
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Tag names are automatically prefixed with `refs/tags/` when stored
|
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in Git, so importing the CVS branch symbol `RELENG-1_0-FINAL` would
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use just `RELENG-1_0-FINAL` for `<name>`, and gfi will write the
|
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use just `RELENG-1_0-FINAL` for `<name>`, and fast-import will write the
|
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corresponding ref as `refs/tags/RELENG-1_0-FINAL`.
|
||||
|
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The value of `<name>` must be a valid refname in Git and therefore
|
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|
@ -553,13 +553,13 @@ The `data` command following `tagger` must supply the annotated tag
|
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message (see below for `data` command syntax). To import an empty
|
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tag message use a 0 length data. Tag messages are free-form and are
|
||||
not interpreted by Git. Currently they must be encoded in UTF-8,
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||||
as gfi does not permit other encodings to be specified.
|
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as fast-import does not permit other encodings to be specified.
|
||||
|
||||
Signing annotated tags during import from within gfi is not
|
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Signing annotated tags during import from within fast-import is not
|
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supported. Trying to include your own PGP/GPG signature is not
|
||||
recommended, as the frontend does not (easily) have access to the
|
||||
complete set of bytes which normally goes into such a signature.
|
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If signing is required, create lightweight tags from within gfi with
|
||||
If signing is required, create lightweight tags from within fast-import with
|
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`reset`, then create the annotated versions of those tags offline
|
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with the standard gitlink:git-tag[1] process.
|
||||
|
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|
@ -611,11 +611,11 @@ however, as marks are inexpensive to store and easy to use.
|
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`data`
|
||||
~~~~~~
|
||||
Supplies raw data (for use as blob/file content, commit messages, or
|
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annotated tag messages) to gfi. Data can be supplied using an exact
|
||||
annotated tag messages) to fast-import. Data can be supplied using an exact
|
||||
byte count or delimited with a terminating line. Real frontends
|
||||
intended for production-quality conversions should always use the
|
||||
exact byte count format, as it is more robust and performs better.
|
||||
The delimited format is intended primarily for testing gfi.
|
||||
The delimited format is intended primarily for testing fast-import.
|
||||
|
||||
Exact byte count format::
|
||||
The frontend must specify the number of bytes of data.
|
||||
|
@ -632,7 +632,7 @@ included in `<count>` and will not be included in the imported data.
|
|||
|
||||
Delimited format::
|
||||
A delimiter string is used to mark the end of the data.
|
||||
gfi will compute the length by searching for the delimiter.
|
||||
fast-import will compute the length by searching for the delimiter.
|
||||
This format is primarly useful for testing and is not
|
||||
recommended for real data.
|
||||
+
|
||||
|
@ -644,14 +644,14 @@ Delimited format::
|
|||
+
|
||||
where `<delim>` is the chosen delimiter string. The string `<delim>`
|
||||
must not appear on a line by itself within `<raw>`, as otherwise
|
||||
gfi will think the data ends earlier than it really does. The `LF`
|
||||
fast-import will think the data ends earlier than it really does. The `LF`
|
||||
immediately trailing `<raw>` is part of `<raw>`. This is one of
|
||||
the limitations of the delimited format, it is impossible to supply
|
||||
a data chunk which does not have an LF as its last byte.
|
||||
|
||||
`checkpoint`
|
||||
~~~~~~~~~~~~
|
||||
Forces gfi to close the current packfile, start a new one, and to
|
||||
Forces fast-import to close the current packfile, start a new one, and to
|
||||
save out all current branch refs, tags and marks.
|
||||
|
||||
....
|
||||
|
@ -659,9 +659,9 @@ save out all current branch refs, tags and marks.
|
|||
LF
|
||||
....
|
||||
|
||||
Note that gfi automatically switches packfiles when the current
|
||||
Note that fast-import automatically switches packfiles when the current
|
||||
packfile reaches \--max-pack-size, or 4 GiB, whichever limit is
|
||||
smaller. During an automatic packfile switch gfi does not update
|
||||
smaller. During an automatic packfile switch fast-import does not update
|
||||
the branch refs, tags or marks.
|
||||
|
||||
As a `checkpoint` can require a significant amount of CPU time and
|
||||
|
@ -672,37 +672,37 @@ several minutes for a single `checkpoint` command to complete.
|
|||
Frontends may choose to issue checkpoints during extremely large
|
||||
and long running imports, or when they need to allow another Git
|
||||
process access to a branch. However given that a 30 GiB Subversion
|
||||
repository can be loaded into Git through gfi in about 3 hours,
|
||||
repository can be loaded into Git through fast-import in about 3 hours,
|
||||
explicit checkpointing may not be necessary.
|
||||
|
||||
|
||||
Tips and Tricks
|
||||
---------------
|
||||
The following tips and tricks have been collected from various
|
||||
users of gfi, and are offered here as suggestions.
|
||||
users of fast-import, and are offered here as suggestions.
|
||||
|
||||
Use One Mark Per Commit
|
||||
~~~~~~~~~~~~~~~~~~~~~~~
|
||||
When doing a repository conversion, use a unique mark per commit
|
||||
(`mark :<n>`) and supply the \--export-marks option on the command
|
||||
line. gfi will dump a file which lists every mark and the Git
|
||||
line. fast-import will dump a file which lists every mark and the Git
|
||||
object SHA-1 that corresponds to it. If the frontend can tie
|
||||
the marks back to the source repository, it is easy to verify the
|
||||
accuracy and completeness of the import by comparing each Git
|
||||
commit to the corresponding source revision.
|
||||
|
||||
Coming from a system such as Perforce or Subversion this should be
|
||||
quite simple, as the gfi mark can also be the Perforce changeset
|
||||
quite simple, as the fast-import mark can also be the Perforce changeset
|
||||
number or the Subversion revision number.
|
||||
|
||||
Freely Skip Around Branches
|
||||
~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
||||
Don't bother trying to optimize the frontend to stick to one branch
|
||||
at a time during an import. Although doing so might be slightly
|
||||
faster for gfi, it tends to increase the complexity of the frontend
|
||||
faster for fast-import, it tends to increase the complexity of the frontend
|
||||
code considerably.
|
||||
|
||||
The branch LRU builtin to gfi tends to behave very well, and the
|
||||
The branch LRU builtin to fast-import tends to behave very well, and the
|
||||
cost of activating an inactive branch is so low that bouncing around
|
||||
between branches has virtually no impact on import performance.
|
||||
|
||||
|
@ -714,7 +714,7 @@ tags which are a subset of the files available in the repository.
|
|||
|
||||
Importing these tags as-is in Git is impossible without making at
|
||||
least one commit which ``fixes up'' the files to match the content
|
||||
of the tag. Use gfi's `reset` command to reset a dummy branch
|
||||
of the tag. Use fast-import's `reset` command to reset a dummy branch
|
||||
outside of your normal branch space to the base commit for the tag,
|
||||
then commit one or more file fixup commits, and finally tag the
|
||||
dummy branch.
|
||||
|
@ -731,12 +731,12 @@ Doing so will allow tools such as gitlink:git-blame[1] to track
|
|||
through the real commit history and properly annotate the source
|
||||
files.
|
||||
|
||||
After gfi terminates the frontend will need to do `rm .git/TAG_FIXUP`
|
||||
After fast-import terminates the frontend will need to do `rm .git/TAG_FIXUP`
|
||||
to remove the dummy branch.
|
||||
|
||||
Import Now, Repack Later
|
||||
~~~~~~~~~~~~~~~~~~~~~~~~
|
||||
As soon as gfi completes the Git repository is completely valid
|
||||
As soon as fast-import completes the Git repository is completely valid
|
||||
and ready for use. Typicallly this takes only a very short time,
|
||||
even for considerably large projects (100,000+ commits).
|
||||
|
||||
|
@ -748,7 +748,7 @@ run the repack in the background and let it finish when it finishes.
|
|||
There is no reason to wait to explore your new Git project!
|
||||
|
||||
If you choose to wait for the repack, don't try to run benchmarks
|
||||
or performance tests until repacking is completed. gfi outputs
|
||||
or performance tests until repacking is completed. fast-import outputs
|
||||
suboptimal packfiles that are simply never seen in real use
|
||||
situations.
|
||||
|
||||
|
@ -764,7 +764,7 @@ project will benefit from the smaller repository.
|
|||
|
||||
Packfile Optimization
|
||||
---------------------
|
||||
When packing a blob gfi always attempts to deltify against the last
|
||||
When packing a blob fast-import always attempts to deltify against the last
|
||||
blob written. Unless specifically arranged for by the frontend,
|
||||
this will probably not be a prior version of the same file, so the
|
||||
generated delta will not be the smallest possible. The resulting
|
||||
|
@ -773,20 +773,20 @@ packfile will be compressed, but will not be optimal.
|
|||
Frontends which have efficient access to all revisions of a
|
||||
single file (for example reading an RCS/CVS ,v file) can choose
|
||||
to supply all revisions of that file as a sequence of consecutive
|
||||
`blob` commands. This allows gfi to deltify the different file
|
||||
`blob` commands. This allows fast-import to deltify the different file
|
||||
revisions against each other, saving space in the final packfile.
|
||||
Marks can be used to later identify individual file revisions during
|
||||
a sequence of `commit` commands.
|
||||
|
||||
The packfile(s) created by gfi do not encourage good disk access
|
||||
patterns. This is caused by gfi writing the data in the order
|
||||
The packfile(s) created by fast-import do not encourage good disk access
|
||||
patterns. This is caused by fast-import writing the data in the order
|
||||
it is received on standard input, while Git typically organizes
|
||||
data within packfiles to make the most recent (current tip) data
|
||||
appear before historical data. Git also clusters commits together,
|
||||
speeding up revision traversal through better cache locality.
|
||||
|
||||
For this reason it is strongly recommended that users repack the
|
||||
repository with `git repack -a -d` after gfi completes, allowing
|
||||
repository with `git repack -a -d` after fast-import completes, allowing
|
||||
Git to reorganize the packfiles for faster data access. If blob
|
||||
deltas are suboptimal (see above) then also adding the `-f` option
|
||||
to force recomputation of all deltas can significantly reduce the
|
||||
|
@ -795,23 +795,23 @@ final packfile size (30-50% smaller can be quite typical).
|
|||
|
||||
Memory Utilization
|
||||
------------------
|
||||
There are a number of factors which affect how much memory gfi
|
||||
There are a number of factors which affect how much memory fast-import
|
||||
requires to perform an import. Like critical sections of core
|
||||
Git, gfi uses its own memory allocators to ammortize any overheads
|
||||
associated with malloc. In practice gfi tends to ammoritize any
|
||||
Git, fast-import uses its own memory allocators to ammortize any overheads
|
||||
associated with malloc. In practice fast-import tends to ammoritize any
|
||||
malloc overheads to 0, due to its use of large block allocations.
|
||||
|
||||
per object
|
||||
~~~~~~~~~~
|
||||
gfi maintains an in-memory structure for every object written in
|
||||
fast-import maintains an in-memory structure for every object written in
|
||||
this execution. On a 32 bit system the structure is 32 bytes,
|
||||
on a 64 bit system the structure is 40 bytes (due to the larger
|
||||
pointer sizes). Objects in the table are not deallocated until
|
||||
gfi terminates. Importing 2 million objects on a 32 bit system
|
||||
fast-import terminates. Importing 2 million objects on a 32 bit system
|
||||
will require approximately 64 MiB of memory.
|
||||
|
||||
The object table is actually a hashtable keyed on the object name
|
||||
(the unique SHA-1). This storage configuration allows gfi to reuse
|
||||
(the unique SHA-1). This storage configuration allows fast-import to reuse
|
||||
an existing or already written object and avoid writing duplicates
|
||||
to the output packfile. Duplicate blobs are surprisingly common
|
||||
in an import, typically due to branch merges in the source.
|
||||
|
@ -831,7 +831,7 @@ of the two classes is significantly different.
|
|||
|
||||
Inactive branches are stored in a structure which uses 96 or 120
|
||||
bytes (32 bit or 64 bit systems, respectively), plus the length of
|
||||
the branch name (typically under 200 bytes), per branch. gfi will
|
||||
the branch name (typically under 200 bytes), per branch. fast-import will
|
||||
easily handle as many as 10,000 inactive branches in under 2 MiB
|
||||
of memory.
|
||||
|
||||
|
@ -846,7 +846,7 @@ As active branches store metadata about the files contained on that
|
|||
branch, their in-memory storage size can grow to a considerable size
|
||||
(see below).
|
||||
|
||||
gfi automatically moves active branches to inactive status based on
|
||||
fast-import automatically moves active branches to inactive status based on
|
||||
a simple least-recently-used algorithm. The LRU chain is updated on
|
||||
each `commit` command. The maximum number of active branches can be
|
||||
increased or decreased on the command line with \--active-branches=.
|
||||
|
@ -867,7 +867,7 @@ tree names are pooled in a common string table, allowing the filename
|
|||
overhead) no matter how many times it occurs within the project.
|
||||
|
||||
The active branch LRU, when coupled with the filename string pool
|
||||
and lazy loading of subtrees, allows gfi to efficiently import
|
||||
and lazy loading of subtrees, allows fast-import to efficiently import
|
||||
projects with 2,000+ branches and 45,114+ files in a very limited
|
||||
memory footprint (less than 2.7 MiB per active branch).
|
||||
|
||||
|
|
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