Throw a NoHeadException when Repository.getFullBranch
returns null
Bug: 351543
Change-Id: I666cd5b67781508a293ae553c6fe5c080c8f4d99
Signed-off-by: Kevin Sawicki <kevin@github.com>
ReceivePack (and PackParser) can be configured with the
maxObjectSizeLimit in order to prevent users from pushing too large
objects to Git. The limit check is applied to all object types
although it is most likely that a BLOB will exceed the limit. In all
cases the size of the object header is excluded from the object size
which is checked against the limit as this is the size of which a BLOB
object would take in the working tree when checked out as a file.
When an object exceeds the maxObjectSizeLimit the receive-pack will
abort immediately.
Delta objects (both offset and ref delta) are also checked against the
limit. However, for delta objects we will first check the size of the
inflated delta block against the maxObjectSizeLimit and abort
immediately if it exceeds the limit. In this case we even do not know
the exact size of the resolved delta object but we assume it will be
larger than the given maxObjectSizeLimit as delta is generally only
chosen if the delta can copy more data from the base object than the
delta needs to insert or needs to represent the copy ranges. Aborting
early, in this case, avoids unnecessary inflating of the (huge) delta
block.
Unfortunately, it is too expensive (especially for a large delta) to
compute SHA-1 of an object that causes the receive-pack to abort.
This would decrease the value of this feature whose main purpose is to
protect server resources from users pushing huge objects. Therefore
we don't report the SHA-1 in the error message.
Change-Id: I177ef24553faacda444ed5895e40ac8925ca0d1e
Signed-off-by: Sasa Zivkov <sasa.zivkov@sap.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Double ' characters are needed for variables to appear in
single quotes. Variables surrounded with a s single ' will
not be replaced when formatted
Change-Id: I0182c1f679ba879ca19dd81bf46924f415dc6003
Signed-off-by: Kevin Sawicki <kevin@github.com>
Exposes essentially the same state machine to the programmer as is
exposed to the client via a ProgressMonitor, using a wrapper around
beginTask()/endTask().
Change-Id: Ic3622b4acea65d2b9b3551c668806981fa7293e3
In practice the DHT storage layer has not been performing as well as
large scale server environments want to see from a Git server.
The performance of the DHT schema degrades rapidly as small changes
are pushed into the repository due to the chunk size being less than
1/3 of the pushed pack size. Small chunks cause poor prefetch
performance during reading, and require significantly longer prefetch
lists inside of the chunk meta field to work around the small size.
The DHT code is very complex (>17,000 lines of code) and is very
sensitive to the underlying database round-trip time, as well as the
way objects were written into the pack stream that was chunked and
stored on the database. A poor pack layout (from any version of C Git
prior to Junio reworking it) can cause the DHT code to be unable to
enumerate the objects of the linux-2.6 repository in a completable
time scale.
Performing a clone from a DHT stored repository of 2 million objects
takes 2 million row lookups in the DHT to locate the OBJECT_INDEX row
for each object being cloned. This is very difficult for some DHTs to
scale, even at 5000 rows/second the lookup stage alone takes 6 minutes
(on local filesystem, this is almost too fast to bother measuring).
Some servers like Apache Cassandra just fall over and cannot complete
the 2 million lookups in rapid fire.
On a ~400 MiB repository, the DHT schema has an extra 25 MiB of
redundant data that gets downloaded to the JGit process, and that is
before you consider the cost of the OBJECT_INDEX table also being
fully loaded, which is at least 223 MiB of data for the linux kernel
repository. In the DHT schema answering a `git clone` of the ~400 MiB
linux kernel needs to load 248 MiB of "index" data from the DHT, in
addition to the ~400 MiB of pack data that gets sent to the client.
This is 193 MiB more data to be accessed than the native filesystem
format, but it needs to come over a much smaller pipe (local Ethernet
typically) than the local SATA disk drive.
I also never got around to writing the "repack" support for the DHT
schema, as it turns out to be fairly complex to safely repack data in
the repository while also trying to minimize the amount of changes
made to the database, due to very common limitations on database
mutation rates..
This new DFS storage layer fixes a lot of those issues by taking the
simple approach for storing relatively standard Git pack and index
files on an abstract filesystem. Packs are accessed by an in-process
buffer cache, similar to the WindowCache used by the local filesystem
storage layer. Unlike the local file IO, there are some assumptions
that the storage system has relatively high latency and no concept of
"file handles". Instead it looks at the file more like HTTP byte range
requests, where a read channel is a simply a thunk to trigger a read
request over the network.
The DFS code in this change is still abstract, it does not store on
any particular filesystem, but is fairly well suited to the Amazon S3
or Apache Hadoop HDFS. Storing packs directly on HDFS rather than
HBase removes a layer of abstraction, as most HBase row reads turn
into an HDFS read.
Most of the DFS code in this change was blatently copied from the
local filesystem code. Most parts should be refactored to be shared
between the two storage systems, but right now I am hesistent to do
this due to how well tuned the local filesystem code currently is.
Change-Id: Iec524abdf172e9ec5485d6c88ca6512cd8a6eafb
Though it may seem less precise, "0 months" looks bad and the reference
Git implementation also does not display "0 months"
Change-Id: I488e9c97656f9941788ae88d7c5c1562ab6c26f0
Adds method into DiffEntry class that allows to specify whether changed
trees are included in scanning result list. By default changed trees
aren't added, but in some cases having changed tree would be useful.
Also adds check for tree count in TreeWalk and when it is different from
two it will thrown an IllegalArgumentException.
This change is required by egit
I7ddb21e7ff54333dd6d7ace3209bbcf83da2b219
Change-Id: I5a680a73e1cffa18ade3402cc86008f46c1da1f1
Signed-off-by: Dariusz Luksza <dariusz@luksza.org>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
When trying to clone into a folder that already contains a cloned
repository native git will fail with a message "fatal: destination path
'folder' already exists and is not an empty directory.". Now JGit will
also fail in this situation throwing a JGitInternalException.
The test case was provided by Tomasz Zarna.
Bug: 347852
Change-Id: If9e9919a5f92d13cf038dc470c21ee5967322dac
Also-by: Tomasz Zarna <Tomasz.Zarna@pl.ibm.com>
Signed-off-by: Adrian Goerler <adrian.goerler@sap.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
If an internal exception occurs while packing and the request
needs to abort, the HTTP response might already be committed due
to progress message having already been delivered to the client.
This prevents UploadPackServlet from resetting the response and
sending back an HTTP 500 response.
Try to catch all exceptions and report internal errors over the
sideband stream or as an ERR command during the initial ACK/NAK
negotiation phase. This allows JGit to transmit an error message
that the user will receive on their console without needing to
worry about resetting the (already gone) HTTP response.
Change-Id: Ie393fb8bb55d2b79ab1276adf71c781c1807f9fe
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
If a fetch or push needs to apply more than a few references
to the local repository it may take more than 0.25 seconds to
process all of the updates. This is especially true in the DHT
storage system during an initial push of a project with many tags.
The backend database may need to use a transaction to ensure each
tag reference creation is unique, and there may be large delays
caused by these transactions.
Change-Id: Ib11a077adfbd525253e425d327f2e2c2380804c7
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
BlameGenerator digs through history and discovers the origin of each
line of some result file. BlameResult consumes the stream of regions
created by the generator and lays them out in a table for applications
to display alongside of source lines.
Applications may optionally push in the working tree copy of a file
using the push(String, byte[]) method, allowing the application to
receive accurate line annotations for the working tree version. Lines
that are uncommitted (difference between HEAD and working tree) will
show up with the description given by the application as the author,
or "Not Committed Yet" as a default string.
Applications may also run the BlameGenerator in reverse mode using the
reverse(AnyObjectId, AnyObjectId) method instead of push(). When
running in the reverse mode the generator annotates lines by the
commit they are removed in, rather than the commit they were added in.
This allows a user to discover where a line disappeared from when they
are looking at an older revision in the repository. For example:
blame --reverse 16e810b2..master -L 1080, org.eclipse.jgit.test/tst/org/eclipse/jgit/storage/file/RefDirectoryTest.java
( 1080) }
2302a6d3 (Christian Halstrick 2011-05-20 11:18:20 +0200 1081)
2302a6d3 (Christian Halstrick 2011-05-20 11:18:20 +0200 1082) /**
2302a6d3 (Christian Halstrick 2011-05-20 11:18:20 +0200 1083) * Kick the timestamp of a local file.
Above we learn that line 1080 (a closing curly brace of the prior
method) still exists in branch master, but the Javadoc comment below
it has been removed by Christian Halstrick on May 20th as part of
commit 2302a6d3. This result differs considerably from that of C
Git's blame --reverse feature. JGit tells the reader which commit
performed the delete, while C Git tells the reader the last commit
that still contained the line, leaving it an exercise to the reader
to discover the descendant that performed the removal.
This is still only a basic implementation. Quite notably it is
missing support for the smart block copy/move detection that the C
implementation of `git blame` is well known for. Despite being
incremental, the BlameGenerator can only be run once. After the
generator runs it cannot be reused. A better implementation would
support applications browsing through history efficiently.
In regards to CQ 5110, only a little of the original code survives.
CQ: 5110
Bug: 306161
Change-Id: I84b8ea4838bb7d25f4fcdd540547884704661b8f
Signed-off-by: Kevin Sawicki <kevin@github.com>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>
Instead of looping over the objectsLists array, always set slot 0 to
null and explicitly work on the 4 indexes that matter. This kills
some loops and increases the length of the code slightly, but I've
always really disliked that dummy 0 slot.
Change-Id: I5ad938501c1c61f637ffdaff0d0d88e3962d8942
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Instead of aborting hard with a server-side exception, report an error
to the client with "ERR %s" in a context where the client is expecting
ACK/NAK. Older clients will report this text to the user, but newer
ones know how to format this message in a more user-friendly way.
Change-Id: I1879b38988ba66f648c069c10dbfa14c3f34adb2
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
The new TransportProtocol type describes what a particular Transport
implementation wants in order to support a connection. 3rd parties
can now plug into the Transport.open() logic by implementing their
own TransportProtocol and Transport classes, and registering with
Transport.register().
GUI applications can help the user configure a connection by looking
at the supported fields of a particular TransportProtocol type, which
makes the GUI more dynamic and may better support new Transports.
Change-Id: Iafd8e3a6285261412aac6cba8e2c333f8b7b76a5
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
This change adds the --only/ -o option to the commit command.
Change-Id: I44352d56877f8204d985cb7a35a2e0faffb7d341
Signed-off-by: Philipp Thun <philipp.thun@sap.com>
Using a resolver and factory pattern for the anonymous git:// Daemon
class makes transport.Daemon more useful on non-file storage systems,
or in embedded applications where the caller wants more precise
control over the work tasks constructed within the daemon.
Rather than defining new interfaces, move the existing HTTP ones
into transport.resolver and make them generic on the connection
handle type. For HTTP, continue to use HttpServletRequest, and
for transport.Daemon use DaemonClient.
To remain compatible with transport.Daemon, FileResolver needs to
learn how to use multiple base directories, and how to export any
Repository instance at a fixed name.
Change-Id: I1efa6b2bd7c6567e983fbbf346947238ea2e847e
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
The most expensive part of packing a repository for transport to
another system is enumerating all of the objects in the repository.
Once this gets to the size of the linux-2.6 repository (1.8 million
objects), enumeration can take several CPU minutes and costs a lot
of temporary working set memory.
Teach PackWriter to efficiently reuse an existing "cached pack"
by answering a clone request with a thin pack followed by a larger
cached pack appended to the end. This requires the repository
owner to first construct the cached pack by hand, and record the
tip commits inside of $GIT_DIR/objects/info/cached-packs:
cd $GIT_DIR
root=$(git rev-parse master)
tmp=objects/.tmp-$$
names=$(echo $root | git pack-objects --keep-true-parents --revs $tmp)
for n in $names; do
chmod a-w $tmp-$n.pack $tmp-$n.idx
touch objects/pack/pack-$n.keep
mv $tmp-$n.pack objects/pack/pack-$n.pack
mv $tmp-$n.idx objects/pack/pack-$n.idx
done
(echo "+ $root";
for n in $names; do echo "P $n"; done;
echo) >>objects/info/cached-packs
git repack -a -d
When a clone request needs to include $root, the corresponding
cached pack will be copied as-is, rather than enumerating all of
the objects that are reachable from $root.
For a linux-2.6 kernel repository that should be about 376 MiB,
the above process creates two packs of 368 MiB and 38 MiB[1].
This is a local disk usage increase of ~26 MiB, due to reduced
delta compression between the large cached pack and the smaller
recent activity pack. The overhead is similar to 1 full copy of
the compressed project sources.
With this cached pack in hand, JGit daemon completes a clone request
in 1m17s less time, but a slightly larger data transfer (+2.39 MiB):
Before:
remote: Counting objects: 1861830, done
remote: Finding sources: 100% (1861830/1861830)
remote: Getting sizes: 100% (88243/88243)
remote: Compressing objects: 100% (88184/88184)
Receiving objects: 100% (1861830/1861830), 376.01 MiB | 19.01 MiB/s, done.
remote: Total 1861830 (delta 4706), reused 1851053 (delta 1553844)
Resolving deltas: 100% (1564621/1564621), done.
real 3m19.005s
After:
remote: Counting objects: 1601, done
remote: Counting objects: 1828460, done
remote: Finding sources: 100% (50475/50475)
remote: Getting sizes: 100% (18843/18843)
remote: Compressing objects: 100% (7585/7585)
remote: Total 1861830 (delta 2407), reused 1856197 (delta 37510)
Receiving objects: 100% (1861830/1861830), 378.40 MiB | 31.31 MiB/s, done.
Resolving deltas: 100% (1559477/1559477), done.
real 2m2.938s
Repository owners can periodically refresh their cached packs by
repacking their repository, folding all newer objects into a larger
cached pack. Since repacking is already considered to be a normal
Git maintenance activity, this isn't a very big burden.
[1] In this test $root was set back about two weeks.
Change-Id: Ib87131d5c4b5e8c5cacb0f4fe16ff4ece554734b
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
CGit pack-objects displays a totals line after the pack data
was fully written. This can be useful to understand some of
the decisions made by the packer, and has been a great tool
for helping to debug some of that code.
Track some of the basic values, and send it to the client when
packing is done:
remote: Counting objects: 1826776, done
remote: Finding sources: 100% (55121/55121)
remote: Getting sizes: 100% (25654/25654)
remote: Compressing objects: 100% (11434/11434)
remote: Total 1861830 (delta 3926), reused 1854705 (delta 38306)
Receiving objects: 100% (1861830/1861830), 386.03 MiB | 30.32 MiB/s, done.
Change-Id: If3b039017a984ed5d5ae80940ce32bda93652df5
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
The first 'Compressing objects' progress message is wrong, its
actually PackWriter looking up the sizes of each object in the
ObjectDatabase, so objects can be sorted correctly in the later
type-size sort that tries to take advantage of "Linus' Law" to
improve delta compression.
Rename the progress to say 'Getting sizes', which is an accurate
description of what it is doing.
Change-Id: Ida0a052ad2f6e994996189ca12959caab9e556a3
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>
After consulting with Christian Halstrick, it turned out that the
handling of rebase during pull was implemented incorrectly.
Change-Id: I40f03409e080cdfeceb21460150f5e02a016e7f4
Signed-off-by: Mathias Kinzler <mathias.kinzler@sap.com>
Instead of offering only a high-level isModified() method a new
method compareMetadata() is introduced which compares a working tree entry
and a index entry by looking at metadata only. Some use-cases
(e.g. computing the content-id in idBuffer()) may use this new method
instead of isModified().
Change-Id: I4de7501d159889fbac5ae6951f4fef8340461b47
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>
The java.io.File.createNewFile() method for creating new empty files
reports failure by returning false. To ease proper checking of return
values provide a utility method wrapping createNewFile() throwing
IOException on failure.
Change-Id: I42a3dc9d8ff70af62e84de396e6a740050afa896
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Merging Git notes branches has several differences from merging "normal"
branches. Although Git notes are initially stored as one flat tree the
tree may fanout when the number of notes becomes too large for efficient
access. In this case the first two hex digits of the note name will be
used as a subdirectory name and the rest 38 hex digits as the file name
under that directory. Similarly, when number of notes decreases a fanout
tree may collapse back into a flat tree. The Git notes merge algorithm
must take into account possibly different tree structures in different
note branches and must properly match them against each other.
Any conflict on a Git note is, by default, resolved by concatenating
the two conflicting versions of the note. A delete-edit conflict is, by
default, resolved by keeping the edit version.
The note merge logic is pluggable and the caller may provide custom
note merger that will perform different merging strategy.
Additionally, it is possible to have non-note entries inside a notes
tree. The merge algorithm must also take this fact into account and
will try to merge such non-note entries. However, in case of any merge
conflicts the merge operation will fail. Git notes merge algorithm is
currently not trying to do content merge of non-note entries.
Thanks to Shawn Pearce for patiently answering my questions related to
this topic, giving hints and providing code snippets.
Change-Id: I3b2335c76c766fd7ea25752e54087f9b19d69c88
Signed-off-by: Sasa Zivkov <sasa.zivkov@sap.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
This is almost reverted cherry-pick, and the implementation is
almost identical. It orders the input to merge differently to get
the effect and produces a different commit message with the
default author, rather than the original author.
Change-Id: I39970091d9f7406ae7168b8efaab23a5e2c16bad
Signed-off-by: Robin Rosenberg <robin.rosenberg@dewire.com>
These settings are stored in <prefix>/etc/gitconfig. The C Git
binary is installed in <prefix>/bin, so we look for the C Git
executable to find this location, first by looking at the PATH
environment variable and then by attemting to launch bash as
a login shell to find out.
Bug: 333216
Change-Id: I1bbee9fb123a81714a34a9cc242b92beacfbb4a8
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Robin Rosenberg <robin.rosenberg@dewire.com>
The java.io.File methods for creating directories report failure by
returning false. To ease proper checking of return values provide
utility methods wrapping mkdir() and mkdirs() which throw IOException
on failure.
Also fix the tests to store test data under a trash folder and cleanup
after test.
Change-Id: I09c7f9909caf7e25feabda9d31e21ce154e7fcd5
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>
For --continue, the Rebase command asserts that there are no unmerged
paths in the current repository. Then it checks if a commit is needed.
If yes, the commit message and author are taken from the author_script
and message files, respectively, and a commit is performed before the
next step is applied.
For --skip, the workspace is reset to the current HEAD before applying
the next step.
Includes some tests and a refactoring that extracts Strings in the
code into constants.
Change-Id: I72d9968535727046e737ec20e23239fe79976179
Signed-off-by: Mathias Kinzler <mathias.kinzler@sap.com>
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>
Provide file helper methods in a reusable utility class to
replace many local implementations. java.io.File has some
methods reporting failure by returning false. We prefer to
throw IOException on failure so that callers can't forget
checking the return value.
Change-Id: I430c77b5d2cffcf8b47584326ad4817a7291845e
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Coverage tests showed that we are missing to test certain areas
in the rebase command. Add the missing tests.
Change-Id: Ia4a272d26cde7e1861dac30496e4b6799fc8187a
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>
Add the ability to checkout a branch to the working tree.
Bug: 330860
Change-Id: Ie06b9e799a9e1be384da0b8996efa7209b32eac3
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>
This is a first iteration to implement Rebase. At the moment, this
does not implement --continue and --skip, so if the first
conflict is found, the only option is to --abort the command.
Bug: 328217
Change-Id: I24d60c0214e71e5572955f8261e10a42e9e95298
Signed-off-by: Mathias Kinzler <mathias.kinzler@sap.com>
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>
This change is based on http://egit.eclipse.org/r/#change,1652
by David Green. The change adds the concept of a CredentialsProvider
which can be registered for git transports and which is
responsible to return credential-related data like passwords and
usernames. Whenenver the transports detects that an authentication
with certain credentials has to be done it will ask the
CredentialsProvider for this data. Foreseen implementations for
such a Provider may be a EGitCredentialsProvider (caching
credential data entered e.g. in the Clone-Wizzard) or a NetRcProvider
(gathering data out of ~/.netrc file).
Bug: 296201
Change-Id: Ibe13e546b45eed3e193c09ecb414bbec2971d362
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>
Signed-off-by: Stefan Lay <stefan.lay@sap.com>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
CC: David Green <dgreen99@gmail.com>
When creating a local branch based on another local branch, the
upstream configuration contains "." as origin and the source branch
as "merge". The PullCommand should support this by skipping the
fetch step altogether and use the base branch to merge with.
Change-Id: I260a1771aeeffca5b0161d1494fd63c672ecc2a6
Signed-off-by: Mathias Kinzler <mathias.kinzler@sap.com>
Implemented the initial version of a cherry-pick command.
A correct error handling is missing (what happens if the
checkout fails, the cherry-pick leads to conflicts etc).
But straightforward cherry-picks works.
Change-Id: I235c0eb3a7a2d5bdfe40400f1deed06f29d746e1
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
The need for branching becomes more pressing with pull
support: we need to make sure the upstream configuration entries
are written correctly when creating and renaming branches
(and of course are cleaned up when deleting them).
This adds support for listing, adding, deleting and renaming
branches including the more common options.
Bug: 326938
Change-Id: I00bcc19476e835d6fd78fd188acde64946c1505c
Signed-off-by: Mathias Kinzler <mathias.kinzler@sap.com>
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>
This is the minimal implementation of a "Pull" command. It does not
have any parameters besides the generic progress monitor and timeout.
It works on the currently checked-out branch and assumes that the
configuration contains the keys "branch.<branch name>.remote" and
"branch.<branch name>.merge" to determine the remote configuration
for the fetch and the remote branch name for the merge.
Bug: 303404
Change-Id: I7fe09029996d0cfc09a7d8f097b5d6af1488fa93
Signed-off-by: Mathias Kinzler <mathias.kinzler@sap.com>
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>
Some strings were not externalized. Also use them in HTTP tests to
ensure that they will also succeed when message bundles are
translated.
Change-Id: Id02717176557e7d57e676e1339cd89f2be88d330
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Projects like org.eclipse.mdt contain large XML files about 6 MiB
in size. So does the Android project platform/frameworks/base.
Doing a clone of either project with JGit takes forever to checkout
the files into the working directory, because delta decompression
tends to be very expensive as we need to constantly reposition the
base stream for each copy instruction. This can be made worse by
a very bad ordering of offsets, possibly due to an XML editor that
doesn't preserve the order of elements in the file very well.
Increasing the threshold to the same limit PackWriter uses when
doing delta compression (50 MiB) permits a default configured
JGit to decompress these XML file objects using the faster
random-access arrays, rather than re-seeking through an inflate
stream, significantly reducing checkout time after a clone.
Since this new limit may be dangerously close to the JVM maximum
heap size, every allocation attempt is now wrapped in a try/catch
so that JGit can degrade by switching to the large object stream
mode when the allocation is refused. It will run slower, but the
operation will still complete.
The large stream mode will run very well for big objects that aren't
delta compressed, and is acceptable for delta compressed objects that
are using only forward referencing copy instructions. Copies using
prior offsets are still going to be horrible, and there is nothing
we can do about it except increase core.streamFileThreshold.
We might in the future want to consider changing the way the delta
generators work in JGit and native C Git to avoid prior offsets once
an object reaches a certain size, even if that causes the delta
instruction stream to be slightly larger. Unfortunately native
C Git won't want to do that until its also able to stream objects
rather than malloc them as contiguous blocks.
Change-Id: Ief7a3896afce15073e80d3691bed90c6a3897307
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>
HistogramDiff is an alternative implementation of patience diff,
performing a search over all matching locations and picking the
longest common subsequence that has the lowest occurrence count.
If there are unique common elements, its behavior is identical to
that of patience diff.
Actual performance on real-world source files usually beats
MyersDiff, sometimes by a factor of 3, especially for complex
comparators that ignore whitespace.
Change-Id: I1806cd708087e36d144fb824a0e5ab7cdd579d73
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Adds API for performing git fetch operations.
Change-Id: Idd95664fd4e3bca03211e4ffda3e354849f92a35
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>
The core.autocrlf variable can take on three values: false, true,
and input. Parsing it as a boolean is wrong, we instead need to
parse a tri-state enumeration.
Add support for parsing and setting enum values from Java from and
to the text based configuration file, and use that to handle the
autocrlf variable.
Bug: 301775
Change-Id: I81b9e33087a33d2ef2eac89ba93b9e83b7ecc223
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Kevin Sawicki
Sasa Zivkov
Dave Borowitz
Shawn O. Pearce
Robin Rosenberg
Tomasz Zarna
Dariusz Luksza
Adrian Goerler
Christoph Brill
Matthias Sohn
Philipp Thun
Chris Aniszczyk
Mathias Kinzler
Christian Halstrick