If you look at any implementation of Comparable in the JDK, you'll see
that the type parameter for Comparable is supposed to be the type of
the implementing class:
http://docs.oracle.com/javase/6/docs/api/java/lang/Comparable.html
The current type signature of Comparable<Object> is pretty awful, at the
very least because you can not, in fact, successfully compare
AnyObjectId with any random subclass of Object. It also causes problems
with type-inference and the scala.math.Ordering trait in Scala.
In order to compile, this change *does* require removing the
AnyObjectId.ompareTo(Object) method - which actually only ever cast
to AnyObjectId in any case. Nothing in the JGit test suite requires this
method, but it might constitute a breaking API change, so it would be
best if it can be added in time for JGit 3.0.
Change-Id: I3b549a5519ccd6785f98e444da76d2363bcbe41a
DiffEntry.getOldId() returns null for a diff without an index line (e.g.
only mode changed, rename without content change).
Bug: 407743
Change-Id: I42eac87421f2a53c985af260a253338f578492bc
There was a severe bug in CommitCommand which could corrupt
repos. When merging an annotated tag the JGit MergeCommand writes
correctly the ID of the tag (and not the id of the commit the tag was
pointing to) into MERGE_HEAD. Native git does the same. But
CommitCommand was reading this file and trusting blindly that it will
contain only IDs of commits. Then the CommitCommand created a
commit which has as parent a non-commit object (the tag object). That's
so corrupt that even native git gives up when you call "git log" in
such a repo.
To reproduce that with EGit simply right-click on a tag in the
Repository View and select Merge. The result was a corrupt repo!
Bug: 336291
Change-Id: I24cd5de19ce6ca7b68b4052c9e73dcc6d207b57c
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
A parenthesis was in the wrong place passing arguments to the wrong
format call. Also fix formatting of enclosing switch statement.
Change-Id: I4cb9642f08b58c39033c3a81dab4bd56bebf4fd2
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
The comment about legacy Tag and Object types no longer applies,
though prior to Idb273d5a92849b42935ac14eed73b796b80aad50 the field
was still being used by RewriteTreeFilter.
Change-Id: I9ee5da8f8a3b61c9cf543817c03117ee0609dd8f
The various rename detection options are an inherent part of the
filter, similar to the path being followed.
This fixes a potential NPE when a RevWalk with a FollowFilter is
created without a Repository, since the old code path tried to get
the DiffConfig from the RevWalk's possibly-missing repository.
Change-Id: Idb273d5a92849b42935ac14eed73b796b80aad50
The most important difference is that in Java7 we have symbolic links
and for most operations in the work tree we want to operate on the link
itself rather than the link target, which the old File methods generally
do.
We also add support for the hidden attribute, which only makes sense
on Windows and exists, just since there are claims that Files.exists
is faster the File.exists.
A new bundle is only activated when run with a Java7 execution
environment. It is implemented as a fragment.
Tycho currently has no way to conditionally include optional features
based on the java version used to run the build, this means with this
change the jgit packaging build always needs to be run using java 7.
Change-Id: I3d6580d6fa7b22f60d7e54ab236898ed44954ffd
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
When either --tags or a tag ref is explicitly specified on fetch, C Git
updates existing local tags if they are different.
Before this change, JGit returned REJECTED in such a case. Now it
updates it and returns FORCED.
Example:
% mkdir a
% cd a
% git init -q
% touch test.txt
% git add test.txt
% git commit -q -m 'Initial'
% git tag v1
% cd ..
% git clone -q a b
% cd a
% echo Test > test.txt
% git commit -q -a -m 'Second'
% git tag -f v1
Updated tag 'v1' (was bc85c08)
% cd ../b
% git fetch --tags
- [tag update] v1 -> v1
Bug: 388095
Change-Id: I5d5494c2ad1a2cdb8e9e614d3de445289734edfe
This corresponds to what C Git does, quoting from the fetch man page:
This is done by first fetching from the remote using the given
<refspec>s, and if the repository has objects that are pointed by
remote tags that it does not yet have, then fetch those missing tags.
Before, JGit would also fetch tags that exist locally but point to a
different object, resulting in REJECTED results for these.
Also add some test cases to cover more cases.
Bug: 388095
Change-Id: Ib03d2d82e9c4b60179d626cfd5174be1da6388b2
Also-by: Stefan Lay <stefan.lay@sap.com>
Depending on the order in which items are traversed for RECURSIVE, an
empty directory may come first before detecting that there is a file and
aborting.
This fixes it by traversing files first.
Bug: 405558
Change-Id: I638b7da58e33ffeb0fee172b96f4c823943d29e9
Signed-off-by: Robin Rosenberg <robin.rosenberg@dewire.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
If the HEAD is not present in a repository, then there is a
NullPointerException thrown in the delete code. Since this only
exists to verify if the deletion is not the HEAD reference, then
skip this check if the HEAD cannot be found.
Bug: 406722
Change-Id: I882497202d986096513a4d791cd07fa935a3f9e4
Signed-off-by: Alex Blewitt <alex.blewitt@gmail.com>
JGit doesn't currently use java.util.logging.Logger. Remove this
never-used Logger introduced in ab99b78ca0 (Implement recursive
merge strategy, 2013-02-21) to make that easier to see.
Change-Id: I92c578e7f3617085a667de7c992174057be3eb71
Adds a new method getConflictingStageStates() which returns a
Map<String, StageState> (path to stage state). StageState is an enum for
all possible stage combinations (BOTH_DELETED, ADDED_BY_US, ...).
This can be used to implement the conflict text for unmerged paths in
output of "git status" or in EGit for decorations/hints.
Bug: 403697
Change-Id: Ib461640a43111b7df4a0debe92ff69b82171329c
Signed-off-by: Chris Aniszczyk <zx@twitter.com>
Instead of counting objects processed, count number of bytes added
into the window. This should rescale the progress meter so that 30%
complete means 30% of the total uncompressed content size has been
inflated and fed into the window.
In theory the progress meter should be more accurate about its
percentage complete/remaining fraction than with objects. When
counting objects small objects move the progress meter more rapidly
than large objects, but demand a smaller amount of work than large
objects being compressed.
Change-Id: Id2848c16a2148b5ca51e0ca1e29c5be97eefeb48
Instead of assuming all objects cost the same amount of time to
delta compress, aggregate the byte size of objects in the list
and partition threads with roughly equal total bytes.
Before splitting the list select the N largest paths and assign
each one to its own thread. This allows threads to get through the
worst cases in parallel before attempting smaller paths that are
more likely to be splittable.
By running the largest path buckets first on each thread the likely
slowest part of compression is done early, while progress is still
reporting a low percentage. This gives users a better impression of
how fast the phase will run. On very complex inputs the slow part
is more likely to happen first, making a user realize its time to
go grab lunch, or even run it overnight.
If the worst sections are earlier, memory overruns may show up
earlier, giving the user a chance to correct the configuration and
try again before wasting large amounts of time. It also makes it
less likely the delta compression phase reaches 92% in 30 minutes
and then crawls for 10 hours through the remaining 8%.
Change-Id: I7621c4349b99e40098825c4966b8411079992e5f
By excluding objects the compactor can avoid storing objects that
are already well packed in the base GC packs, or any other pack
not being replaced by the current compaction operation.
For deltas the base object is still included even if the base exists
in another exclusion set. This favors keeping deltas for recent
history, to support faster fetch operations for clients.
Change-Id: Ie822fe075fe5072fe3171450fda2f0ca507796a1
Use recursive merge as the default strategy since it can successfully
merge more cases than the resolve strategy can. This is also the default
in native Git.
Change-Id: I38fd522edb2791f15d83e99038185edb09fed8e1
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Previously, the code assumed all commits in the old pack would also
be present in the new pack. This assumption caused an
ArrayIndexOutOfBoundsException during remapping of ids. Fix the
iterator to only return entries that may be remapped. Furthermore,
update getBitmap() to return null if commit does not exist in the
new pack.
Change-Id: I065babe8cd39a7654c916bd01c7012135733dddf
This fixes some problems with inputs around the size of the internal
buffer in AutoCRLFOutputStream (8000).
Tests supplied by Robin Stocker.
Bug: 405672
Change-Id: I6147897290392b3bfd4040e8006da39c302a3d49
If reuseObjects=true but reuseDeltas=false the caller wants attempt
a delta for every object in the input list. Test for reuseDeltas
to ensure every object passes through the searchInWindow() method.
If no delta is possible for an object and it will be stored whole
(non-delta format), PackWriter may still reuse its content from any
source pack. This avoids an inflate()-deflate() cycle to recompress
the object contents.
Change-Id: I845caeded419ef4551ef1c85787dd5ffd73235d9
TemporaryBuffer is great when the output size is not known, but must
be bound by a relatively large upper limit that fits in memory, e.g.
64 KiB or 20 MiB. The buffer gracefully supports growing storage by
allocating 8 KiB blocks and storing them in an ArrayList.
In a Git repository many deltas are less than 8 KiB. Typical tree
objects are well below this threshold, and their deltas must be
encoded even smaller.
For these much smaller cases avoid the 8 KiB minimum allocation used
by TemporaryBuffer. Instead allocate a very small OutputStream
writing to an array that is sized at the limit.
Change-Id: Ie25c6d3a8cf4604e0f8cd9a3b5b701a592d6ffca
Nicolas Pitre discovered a very simple rule for selecting between two
different delta base candidates:
- if based whole object, must be <= 50% of target
- if at end of a chain, must be <= 1/depth * 50% of target
The rule penalizes deltas near the end of the chain, requiring them to
be very small in order to be kept by the packer. This favors deltas
that are based on a shorter chain, where the read-time unpack cost is
much lower. Fewer bytes need to be consulted from the source pack
file, and less copying is required in memory to rebuild the object.
Junio Hamano explained Nico's rule to me today, and this commit fixes
DeltaWindow to implement it as described.
When no base has been chosen the computation is simply the statements
denoted above. However once a base with depth of 9 has been chosen
(e.g. when pack.depth is limited to 10), a non-delta source may
create a new delta that is up to 10x larger than the already selected
base. This reflects the intent of Nico's size distribution rule no
matter what order objects are visited in the DeltaWindow.
With this patch and my other patches applied, repacking JGit with:
[pack]
reuseObjects = false
reuseDeltas = false
depth = 50
window = 250
threads = 4
compression = 9
CGit (all) 5,711,735 bytes; real 0m13.942s user 0m47.722s [1]
JGit heads 5,718,295 bytes; real 0m11.880s user 0m38.177s [2]
rest 9,809 bytes
The improved JGit result for the head pack is only 6.4 KiB larger than
CGit's resulting pack. This patch allowed JGit to find an additional
39.7 KiB worth of space savings. JGit now also often runs 2s faster
than CGit, despite also creating bitmaps and pruning objects after the
head pack creation.
[1] time git repack -a -d -F --window=250 --depth=50
[2] time java -Xmx128m -jar jgit debug-gc
Change-Id: I5caec31359bf7248cabdd2a3254c84d4ee3cd96b
When an idle thread tries to steal work from a sibling's remaining
toSearch queue, always try to split along a path boundary. This
avoids missing delta opportunities in the current window of the
thread whose work is being taken.
The search order is reversed to walk further down the chain from
current position, avoiding the risk of splitting the list within
the path the thread is currently processing.
When selecting which thread to split from use an accurate estimate
of the size to be taken. This avoids selecting a thread that has
only one path remaining but may contain more pending entries than
another thread with several paths remaining.
As there is now a race condition where the straggling thread can
start the next path before the split can finish, the stealWork()
loop spins until it is able to acquire a split or there is only
one path remaining in the siblings.
Change-Id: Ib11ff99f90a4d9efab24bf4a85342cc63203dba5
PackWriter generally chooses the order for objects when it builds the
object lists. This ordering already depends on history information to
guide placing more recent objects first and historical objects last.
Allow PackWriter to make the basic ordering decisions, instead of
trying to override them. The old approach of sorting the list caused
DfsReader to override any ordering change PackWriter might have tried
to make when repacking a repository.
This now better matches with WindowCursor's implementation, where
PackWriter solely determines the object ordering.
Change-Id: Ic17ab5631ec539f0758b962966c3a1823735b814
Typical window sizes are 10 and 250 (although others are accepted).
In either case the pointer overhead of 1 pointer in an array or
2 pointers for a double linked list is trivial. A doubly linked
list as used here for window=250 is only another 1024 bytes on a
32 bit machine, or 2048 bytes on a 64 bit machine.
The critical search loops scan through the array in either the
previous direction or the next direction until the cycle is finished,
or some other scan abort condition is reached. Loading the next
object's pointer from a field in the current object avoids the
branch required to test for wrapping around the edge of the array.
It also saves the array bounds check on each access.
When a delta is chosen the window is shuffled to hoist the currently
selected base as an earlier candidate for the next object. Moving
the window entry is easier in a double-linked list than sliding a
group of array entries.
Change-Id: I9ccf20c3362a78678aede0f0f2cda165e509adff
The copy instruction formatter should not to compute the shifts and
masks twice. Instead compute them once and assume there is a register
available to store the temporary "b" for compare with 0.
Change-Id: Ic7826f29dca67b16903d8f790bdf785eb478c10d
javac and the JIT are more likely to understand a boolean being
used as a branch conditional than comparing int against 0 and 1.
Rewrite NEXT_RES and NEXT_SRC constants to be booleans so the
code is clarified for the JIT.
Change-Id: I1bdd8b587a69572975a84609c779b9ebf877b85d
Instead of using a compare-with-0 use a does not equal 0.
javac bytecode has a special instruction for this, as it
is very common in software. We can assume the JIT knows
how to efficiently translate the opcode to machine code,
and processors can do != 0 very quickly.
Change-Id: Idb84c1d744d2874517fd4bfa1db390e2dbf64eac
This class and all of its methods are only package visible.
Clarify the methods as final for the benefit of the JIT to
inline trivial code.
Change-Id: I078841f9900dbf299fbe6abf2599f0208ae96856
Colby just pointed out to me the buffer was 16 KiB. This may
be very small for common objects. Increase to 64 KiB.
Change-Id: Ideecc4720655a57673252f7adb8eebdf2fda230d
Most objects are written as OFS_DELTA with the base in the pack,
that is why this case comes first in writeHeader(). Rewrite the
condition to always examine this first and cache the PackWriter's
formatting flag for use of OFS_DELTA headers, in modern Git networks
this is true more often then it it is false.
Assume the cost of write() is high, especially due to entering the
MessageDigest to update the pack footer SHA-1 computation. Combine
the OFS_DELTA information as part of the header buffer so that the
entire burst is a single write call, rather than two relatively
small ones. Most OFS_DELTA headers are <= 6 bytes, so this rewrite
tranforms 2 writes of 3 bytes each into 1 write of ~6 bytes.
Try to simplify the objectHeader code to reduce branches and use
more local registers. This shouldn't really be necessary if the
compiler is well optimized, but it isn't very hard to clarify data
usage to either javac or the JIT, which may make it easier for the
JIT to produce better machine code for this method.
Change-Id: I2b12788ad6866076fabbf7fa11f8cce44e963f35
update(int) is only invoked from a worker thread, in JGit's case
this is DeltaTask. The Javadoc of TSPM suggests update should only
ever be used by a worker thread.
Skip the main thread check, saving some cycles on each run of the
progress monitor.
Change-Id: I6cb9382d71b4cb3f8e8981c7ac382da25304dfcb
These methods cannot be sanely overridden anywhere. Most methods
are package visible only, or are private. A few public methods do
exist but there is no useful way to override them since creation
of PackOutputStream is managed by PackWriter and cannot be delegated.
Change-Id: I12cd3326b78d497c1f9751014d04d1460b46e0b0
Roberto Tyley
Robin Stocker
Christian Halstrick
Robin Rosenberg
Matthias Sohn
Dave Borowitz
Alex Blewitt
Jonathan Nieder
Shawn Pearce
Shawn Pearce
Colby Ranger