During a review of the class, Josh Bloch pointed out we can use
"i = (i + 1) & mask" to wrap around at the end of the table, instead
of a conditional with a branch. This is generally faster due to one
less branch that will be mis-predicted by the CPU.
Change-Id: Ic88c00455ebc6adde9708563a6ad4d0377442bba
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
* changes:
ObjectIdSubclassMap: Avoid field loads in inner loops
ObjectIdSubclassMap: Manually inline index()
ObjectIdSubclassMap: Change initial size to 2048
ObjectIdSubclassMap: Grow before insertions
ObjectIdSubclassMap: Use & rather than % for hashing
readPipe() may consume rather much time, so
gitPrefix should be cached. If the git executable changes,
users should run FS.detect() again to get a new
instance of FS_Win32.
Ensure the JIT knows the table cannot be changed during the critical
inner loop of get() or insert() by loading the field into a final
local variable. This shouldn't be necessary, but the instance member
is declared non-final (to resizing) and it is not very obvious to the
JIT that the table cannot be modified by AnyObjectId.equals().
Simplify the JIT's decision making by making it obvious, these
values cannot change during the critical inner loop, allowing
for better register allocation.
Change-Id: I0d797533fc5327366f1207b0937c406f02cdaab3
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
This method is trivial in definition, and is called in only 3
places. Inline the method manually to ensure its really going
to be inlined by the JIT at runtime.
Change-Id: I128522af8167c07d2de6cc210573599038871dda
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
32 is way to small for the map. Most applications using the map
will need to load more than 16 objects just from the root refs
being read from the Repository.
Default the initial size to 2048. This cuts out 6 expansions in
the early life of the table, reducing garbage and rehashing time.
Change-Id: I6dd076ebc0b284f1755855d383b79535604ac547
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
If the table needs to be grown, do it before the current insertion
rather than after. This is a tiny micro-optimization that allows
the compiler to reuse the result of "++size" to compare against
previously pre-computed size at which the table should rehash itself.
Change-Id: Ief6f81b91c10ed433d67e0182f558ca70d58a2b0
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Bitwise and is faster than integer modulus operations, and since
the table size is always a power of 2, this is simple to use for
index operation.
Change-Id: I83d01e5c74fd9e910c633a98ea6f90b59092ba29
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
obj_hash doesn't match our naming conventions, camelCaseNames
are the preferred format.
Change-Id: I72da199daccb60a98d17b6af1e498189bf149515
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
A standard HashSet was being used to store the list of subsections as
they were being parsed. This was changed to use a LinkedHashSet so
that iterating over the set would return values in the same order as
they are listed in the config file.
Change-Id: I4251f95b8fe0ad59b07ff563c9ebb468f996c37d
Javadoc for ScheduledThreadPoolExecutor says [1]:
While ScheduledThreadPoolExecutor inherits from ThreadPoolExecutor, a
few of the inherited tuning methods are not useful for it. In
particular, because it acts as a fixed-sized pool using corePoolSize
threads and an unbounded queue, adjustments to maximumPoolSize have no
useful effect.
[1]
http://download.oracle.com/javase/6/docs/api/java/util/concurrent/ScheduledThreadPoolExecutor.html
Change-Id: I8eccb7d6544aa6e27f5fa064c19dddb2a706523f
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Instead of resizing an ArrayList until all objects have been added,
append objects into a specialized List type that uses small arrays
of 1024 entries for each 1024 objects added.
For a large repository like linux-2.6, PackWriter will now allocate
1,758 smaller arrays to hold the object list, without creating any
garbage from the intermediate states due to list expansion.
1024 was chosen as the block size (and initial directory size) as this
is a reasonable balance for the PackWriter code. Each block uses
approximately 4096 bytes in a 32 bit JVM, as does the default top
level block directory. The top level directory doesn't expand until 1
million items have been added to the list, which for linux-2.6 won't
yet occur as the lists are per-object-type and are thus bounded to
about 1/3 of 1.8 million.
Change-Id: If9e4092eb502394c5d3d044b58cf49952772f6d6
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
The mapTree() routines have been deprecated for a long time, and their
sibilings for mapCommit() and mapTag() were already removed from the
main Repository API.
Remove mapTree(). Application callers who only need the tree's name
can use resolve("^{tree}") syntax to resolve to the tree ObjectId, or
fail if the input is not a tree.
Applications that want to read a tree should use DirCache or TreeWalk.
Change-Id: I85726413790fc87721271c482f6636f81baf8b82
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
This type and its associated methods has been deprecated for a while
now. Time to remove it. Applications can use a TreeWalk instead to
access the elements of any tree-like object.
Change-Id: I047e552ac77b77e2de086f63cb4fb318da57c208
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
This interface has been deprecated for a while now.
Applications can use a TreeWalk instead.
Change-Id: I751d6e919e4b501c36fc36e5f816b8a8c5379cb9
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
This has been deprecated for some time now. Applications should
instead use DirCache within a TreeWalk.
Change-Id: I8099d93f07139c33fe09bdeef8d739782397da17
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
This class has been deprecated for a long time now.
Time to remove it. Applications can use the newer
DirCache.writeTree() as a replacement.
Change-Id: I91dc9507668d8a3ecadd6acd4f1c8b7bd7760cc3
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
This class has been deprecated for a long time now.
Time to remove it. Applications can use the newer
DirCacheCheckout class as a replacement.
Change-Id: Id66d29fcca5a7286b8f8838303d83f40898918d2
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
This interface has been deprecated for a long time now.
Time to remove it.
Change-Id: I29a938657e4637b2a9d0561940b38d70866613f7
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
When I disabled validation I broke the code that handled copying small
objects whose contents were below 8192 bytes in size but spanned over
the end of one window and into the next window. These objects did not
ever populate the temporary write buffer, resulting in garbage writing
into the output stream instead of valid object contents.
Change-Id: Ie26a2aaa885d0eee4888a9b12c222040ee4a8562
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
When fetch TagOpt is AUTO_FOLLOW do not follow refs/tags/ names that
point directly to commits which are on unreleated side branches.
Change-Id: Iea6eee5a05ae7402a7f256fd9c1e3d3b5ccb58dd
Reported-by: Slawomir Ginter <sginter@atlassian.com>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
During unit tests and most likely elsewhere, updates come too fast for
a simple timestamp comparison (with one seconds resolution) to work.
I.e. DirCache thinks it hasn't changed.
Use FileSnapshot instead which has more advanced logic.
Change-Id: Ib850f84398ef7d4b8a8a6f5a0ae6963e37f2b470
Signed-off-by: Robin Rosenberg <robin.rosenberg@dewire.com>
When parsing a string such as "foo-gbed2" resolve() was assuming the
suffix was from git describe output. This lead to JGit trying to find
the completion for the object abbreviation "bed2", rather than using
the current value of the reference. If there was only one such object
in the repository, JGit might actually use the wrong value here, as
resolve() would return the completion of the abbreviation "bed2"
rather than the current value of the reference "refs/heads/foo-gbed2".
Move the parsing of git describe abbreviations out of the operator
portion of the resolve() method and into the simple portion that is
supposed to handle only object ids or reference names, and only do the
describe parsing after all other approaches have already failed to
provide a resolution.
Add new unit tests to verify the behavior is as expected by users.
Bug: 338839
Change-Id: I52054d7b89628700c730f9a4bd7743b16b9042a9
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Applications may already have a Ref or ObjectId on hand that they want
the remote to be updated to. Instead of converting these into a
String and relying on the parsing rules of resolve(), allow the
application to supply the Ref or ObjectId directly.
Bug: 338839
Change-Id: If5865ac9eb069de1c8f224090b6020fc422f9f12
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
If object reuse validation is enabled, the output pack is going to
probably be stored locally. When reusing an existing cached pack
to save object enumeration costs, ensure the cached pack has not
been corrupted by checking its SHA-1 trailer. If it has, writing
will abort and the output pack won't be complete. This prevents
anyone from trying to use the output pack, and catches corruption
before it can be carried any further.
Change-Id: If89d0d4e429d9f4c86f14de6c0020902705153e6
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
There is no need to validate the object contents during
copyObjectAsIs if the result is going to be parsed by unpack-objects
or index-pack. Both programs will compute the SHA-1 of the object,
and also validate most of the pack structure. For git daemon
like servers, this work is already done on the client end of the
connection, so the server doesn't need to repeat that work itself.
Disable object validation for the 3 transport cases where we know
the remote side will handle object validation for us (push, bundle
creation, and upload pack). This improves performance on the server
side by reducing the work that must be done.
Change-Id: Iabb78eec45898e4a17f7aab3fb94c004d8d69af6
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Annotated tags need to be parsed by many viewing tools, but putting
them at the end of the pack hurts because kernel prefetching might
not have loaded them, since they are so far from the commits they
reference.
Position tags right behind the commits, but before the trees.
Typically the annotated tag set for a repository is very small,
so the extra prefetch burden it puts on tools that don't need
annotated tags (but do need commits and trees) is fairly low.
Change-Id: Ibbabdd94e7d563901c0309c79a496ee049cdec50
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
This simple refactoring makes it easier to pre-process each of the
object lists before its handed into the actual write routine.
Change-Id: Iea95e5ecbc7374f6bcbb43d1c75285f4f564d09d
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
JGit doesn't generate deltas for commit or tag objects when it packs
a repository from scratch. This is an explicit design decision that
is (mostly) justified by the fact that these objects do not delta
compress well.
Annotated tags are made once on stable points of the project history,
it is unlikely they will ever appear again with sufficient common
text to justify using a delta over just deflating the raw content.
JGit never tries to delta compress annotated tags and I take the
stance that these are best stored as non-deltas given how frequently
they might be accessed by repository viewers.
Commits only have sufficient common text when they are cherry-picked
to forward-port or back-port a change from one branch to another.
Even in these cases the distance between the commits as returned
by the log traversal has to be small enough that they would both
appear in the delta search window at the same time in order to
delta compress one of the messages against the other. JGit never
tries to delta compress commits, as it requires a lot of CPU time
but typically does not produce a smaller pack file.
Avoid reusing deltas for either of these types when constructing a
new pack. To avoid killing performance during serving of network
clients, UploadPack disables this code change by allowing PackWriter
to reuse delta commits. Repositories that were already repacked by
C Git will not have their delta commits decompressed and recompressed
on the fly during object writing, saving server-side CPU resources.
Change-Id: I749407e7c5c677e05e4d054b40db7656cfa7fca8
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
This is a tiny optimization to how delta search works. Checking for
isReuseAsIs() avoids doing delta compression search on non-delta
objects already stored in packs within the repository. Such objects
are not likely to be delta compressable, as they were already delta
searched when their containing pack was generated and they were
not delta compressed at that time. Doing delta compression now is
unlikely to produce a different result, but would waste a lot of CPU.
The isReuseAsIs() flag is checked before isDoNotDelta() because it
is very common to reuse objects in the output pack. Most objects
get reused, and only a handful have the isDoNotDelta() bit set.
Moving the check earlier allows the loop to more quickly skip
through objects that will never need to be considered.
Change-Id: Ied757363f775058177fc1befb8ace20fe9759bac
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
The alarm queue threads were started with an empty task body, which
meant the thread started and terminated immediately, leaving the
queue itself with no worker.
Change-Id: I2a9b5fe9c2bdff4a5e0f7ec7ad41a54b41a4ddd6
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Instead of polling the system clock on every update(1) method call,
use a scheduled executor to toggle a volatile once per second until
the task is done. Check the volatile on each update(int), looking
to see if output should occur.
This limits progress output to either once per 1% complete, or once
per second. To save time during update calls the timer isn't reset
during each 1% of output, which means we may see one unnecessary
output trigger if at least 1% completed during the one second of the
alarm time.
Change-Id: I8fdd7e31c37bef39a5d1b3da7105da0ef879eb84
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Checkout of remote tracking branch failed when no local branch
existed. Also enhance RepositoryTestCase to enable checking index
state of another test repository.
Bug: 337695
Change-Id: Idf4c05bdf23b5161688818342b2bf9a45b49f479
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
JDK7 changed behavior slightly on some InputStream types, resulting in
the first read being shorter than the count requested. That caused us
to overwrite the earlier part of the buffer with later data, as the
offset index wasn't updated in the loop.
Fix the loop to increment offset by the number of bytes read in this
iteration, so the next read appends to the buffer rather than doing an
overwrite.
Bug: 338119
Change-Id: I222fb2f993cd9b637b6b8d93daab5777ef7ec7a6
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
FetchCommand now does not set a null credentials provider on
Transport because in this case the default provider is replaced with
null and the default mechanism for providing credentials is not
working.
Change-Id: I44096aa856f031545df39d4b09af198caa2c21f6
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
In bc1af8459e ("RevWalk: Don't reset ObjectReader when stopping") we
stopped releasing the reader when the current log traversal is over.
This should have also been applied to the merge base logic that is
buried within MergeGenerator, but got missed.
Change-Id: I8328f43f02cba06fd545e22134872e781b9d4d36
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Also use FS.resolve() to properly resolve files from path strings.
Bug: 328428 (partial fix)
Change-Id: I41d94694f220dcb85605c9acadfffb1fa23beaeb
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
We did not record the time spent on the object reuse search or the
object size lookup, both of which occur between the counting phase and
the compressing phase. If there are enough objects involved, these
times can be significant so its worth timing them and recording it.
Change-Id: I89084acfc598bb6533d75d90cb8de459f0ed93be
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Support for --no-standard-notes and --show-notes=REF options is added
to the Log command. The --show-notes option can be specified more than
once if more than one notes branch should be used for showing notes.
The notes are displayed from note branches in the order how the note
branches are specified in the command line. However, the standard note,
from the refs/notes/commits, is always displayed as first unless
the --no-standard-notes options is given.
Change-Id: I4e7940804ed9d388b625b8e8a8e25bfcf5ee15a6
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>
The total delta count is supposed to include reused deltas, not
just newly created deltas.
Change-Id: I98cbdcef80d59714a4f62ff322e7b709b08b6d26
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Many source browsers and network related tools like UploadPack need
to find and parse the target of all branches and annotated tags
within the repository during their startup phase. Clustering these
together into the same part of the pack file will improve locality,
reducing thrashing when an application starts and needs to load
all of these into memory at once.
To prevent bottlenecking basic log viewing tools that are scannning
backwards from the tip of a current branch (and don't need tags)
we place this cluster of older targets after 4096 newer commits
have already been placed into the pack stream. 4096 was chosen as
a rough guess, but was based on a few factors:
- log viewers typically show 5-200 commits per page
- users only view the first page or two
- DHT can cram 2200-4000 commits per 1 MiB chunk
thus these will fall into the second commit chunk (roughly)
Unfortunately this placement hurts history tools that are scanning
backwards through the commit graph and completely ignored tags or
branch heads when they started.
An ancient tagged commit is no longer positioned behind its first
child (its now much earlier), resulting in a page fault for the
parser to reload this cluster of objects on demand. This may be
an acceptable loss. If a user is walking backwards and has already
scanned through more than 4096 commits of history, waiting for the
region to reload isn't really that bad compared to the amount of
time already spent.
If the repository is so small that there are less than 4096 commits,
this change has no impact on the placement of objects.
Change-Id: If3052e430d305e17878d94145c93754f56b74c61
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
If the underlying storage has a high latency per SHA-1 lookup
(e.g. the DHT support we are working on), parsing each wanted
annotated tag object back to its underlying commit is too slow,
its a sequential lookup for each tag. With hundreds of tags in
a repository this takes far too long.
Instead queue up a list of the tags whose objects need to be found,
and then locate all of those in one parseAny batch. This works
for the common case of annotated tag to single tree or commit.
For the less often used tag->tag->commit, it at least gets us
one level parsed in the larger batch before we have to go back to
sequential lookups.
Change-Id: I94beef3f14281406f15c8cf9fa02d83faf102a19
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
If the CachedPack knows its delta count, we need to increment both
the totalDeltas and reusedDeltas fields of the stats object.
Change-Id: I70113609c22476ce7f1e4d9a92f486e9b0f59e44
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
If one or more cached packs fully covers the request, don't bother
with looking up the objects and trying to walk the graph. Just use
the cached packs and return immediately.
This helps clones of quiet repositories that have not been modified
since their last repack, its likely the cached packs are accurate
and no graph walking is required.
Change-Id: I9062a5ac2f71b525322590209664a84051fd5f8a
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
CGit just learned to always use OFS_DELTA when writing out bundle
files. This makes sense because bundle came about well after
OFS_DELTA was established, so any version of CGit that can read a
bundle file can also read OFS_DELTA. Since OFS_DELTA is smaller,
always use it when writing bundles.
Change-Id: I44f9921494798ea0c99e16eab58b87bebeb9aff5
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
RevWalk in JGit and the revision code in C Git both parse commits out
of the pack file in an order that differs from strict timestamp and
topological sorting. Both implementations pop a commit from the head
of a date queue, and then immediately parse all of its parents in
order to insert those into the date queue at the proper positions as
determined by their committer timestamp field. This implies that the
parents are parsed when their most recent child is popped from the
queue, and not where they are popped during traversal.
Hoisting a parent commit to be immediately behind its child improves
locality by making sure all parents of a merge are clustered together,
and thus can be paged into the parser by the pack file buffering
system (aka WindowCache in JGit) together.
Change-Id: I80f9e64cafa2e8f082776b43845edf23065386a2
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Previously, this method would not (always) work when a recursive path
such as "a/b" was passed into it.
Change-Id: I0752a1f5fc7fef32064d8f921b33187c0bdc7227
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>
A checked Exception is thrown instead.
The reason for throwing an Exception is that the state of the
repository is inconsistent in this case: There is a merge
configuration containing a non-existing local branch. Ideally the
deletion of a local branch should also delete the corresponding
merge configuration.
Bug: 337315
Change-Id: I71e56ffb90e11e6e3c1bbd964ad63972d67990c0
Signed-off-by: Stefan Lay <stefan.lay@sap.com>
As PackParser supports a progress meter for the "Resolving deltas"
phase of its work, we should export this to smart HTTP clients so
they know the server is still working on their (large) upload.
However this isn't as simple as just dropping in a binding for
the SmartOutputStream to flush when its told to. We want to
avoid spurious flushes triggered by the use of sideband, or the
status report formatting in the send-pack/receive-pack protocol.
Change-Id: Ibd88022a298c5fed0edb23dfaf2e90278807ba8b
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
If a cached pack is used, it might know how many deltas are contained
within it. Record that count as part of our reusedDeltas field
for the stats line we show clients.
Change-Id: I1c61fb817305a95eeac654cccf132cba20b2339c
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Like ReceivePack, callers that embed UploadPack within their
service may wish to see the set of references that were sent
to the client. We already have the map on hand, it just needs
to be exposed with a getter.
Change-Id: I123b23e475860d5bb968906bef59068985088b7b
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
The setMustExist() method allows callers to require the repository
exists in order for build() to succeed. This is useful within a
RepositoryResolver where existence is required.
Change-Id: I6a1154551435cf0da6c2b4a7f4dce266abea5dff
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.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 UploadPackLogger interface allows applications that embed
GitServlet or otherwise use UploadPack to service clients to
track and log how PackWriter was used, and what it sent. This
provides more granularity into the request activity than might
be available from the HTTP server logs, helping administrators
to better understand utilization and Git server performance.
Change-Id: I1d36b060eb3385339d5f986e68192789ef70fc4e
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
If the RevFilter doesn't actually require the commit body,
we shouldn't reparse it if the body was disposed. This happens
often inside of UploadPack during common ancestor negotation, the
RevWalk is reset and re-run over roughly the same commit space,
but the bodies are discarded because the commit message is not
relevant to the process.
Change-Id: I87b6b6a5fb269669867047698abf718d366bd002
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Applications like UploadPack reset() and reuse the same RevWalk
multiple times in very rapid succession. Releasing the ObjectReader's
internal state on each use, only to allocate it again on the next
cycle kills performance if the ObjectReader has internal caches, or
even if the Inflater gets returned and pulled from the InflaterCache
too frequently.
Making releasing the ObjectReader the application's responsibility
when it is done with the RevWalk, which most already do by wrapping
their loop in a try/finally block.
Change-Id: I3ad188a719e8d7f6bf27d1a7ca16d465534713f4
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
When UploadPack has computed the merge base between the client's have
set and the want set, its already loaded and parsed all of the
interesting commits that PackWriter needs to transmit to the client.
Switching the RevWalk and its object pool over to be an ObjectWalk
saves PackWriter from needing to re-parse these same commits from the
ObjectDatabase, reducing the startup latency for the enumeration
phase of packing.
UploadPack doesn't want to use an ObjectWalk for the okToGiveUp()
tests because its slower, during each commit popped it needs to cache
the tree into the pendingObjects list, and during each reset() it
discards a bunch of ObjectWalk specific state and reallocates some
internal collections. ObjectWalk was never meant to be rapidly
reset() like UploadPack does, so its perhaps somewhat cleaner to allow
"upgrading" a RevWalk to an ObjectWalk.
Bug: 301639
Change-Id: I97ef52a0b79d78229c272880aedb7f74d0f7532f
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
The peeled reference information for tags is more efficient to
work with than parsing the tag objects, as usually its coming from
the packed-refs file, which stores the peeled information for us.
Rely on the peeled information to decide if the tag should be
included or not, instead of using our RevWalk to parse the object.
Change-Id: I6714a8560a1c04b5578e9c5b469ea3c77188dff3
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
When negotiate() starts there is at least one want, but no haves, and
thus no common base exists. Its not ok to give up yet, the client
should try to find a common base with the server. Avoid scanning our
history along the want chains until we have found at least one commit
in common with the client, this will trigger okToGiveUp to be set to
null, enabling okToGiveUp() to perform the scan.
Bug: 301639
Change-Id: I98a82a5424fd4c9995924375c7910f76ca4f03af
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
If the client presents a common commit on a side branch, and there is
a want for a disconnected branch UploadPack was walking back on the
entire history of the disconnected branch because it never would find
the common commit.
Limit our search back along any given want to be no earlier than the
oldest common commit received via a "have" line from our client. This
prevents us from looking at all of the project history.
Bug: 301639
Change-Id: Iffaaa2250907150d6efa1cf2f2fcf59851d5267d
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>
isOutdated returns true iff the memory state differs from the index
file.
Change-Id: If35db06743f5f588ab19d360fd2a18a07c918edb
Signed-off-by: Jens Baumgart <jens.baumgart@sap.com>
When pulling into a local branch that has no upstream configuration,
pull should try to used the default remote ("origin") instead of
throwing an Exception.
Bug: 336504
Change-Id: Ife75858e89ea79c0d6d88ba73877fe8400448e34
Signed-off-by: Mathias Kinzler <mathias.kinzler@sap.com>
If the command contains spaces, it needs to be evaluated by the remote
shell. Quoting the command breaks this, making it impossible to run a
remote command that needs additional options.
Bug: 336301
Change-Id: Ib5d88f0b2151df2d1d2b4e08d51ee979f6da67b5
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
This gets non-commits out of the wantSatisfied() main loop by making
use of the cached SATISIFIED flag and its existing bypass. Anything
that isn't a commit cannot be discovered by the have negotiation, so
its always assumed to be SATISIFIED by the server.
Bug: 301639
Change-Id: I1ef354fbf2e2ed44c9020a4069d7179f2159f19f
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
When the walker resets, its going to scrub the COMMON and SATISIFIED
flags off a commit if the commit is contained within another commit
the client wants. This is common if the client asks for both a
'maint' and 'master' branch, and 'maint' is also fully merged into
'master'.
COMMON shouldn't be scrubbed during reset because its used to control
membership of the commonBase collection, which is a List. commonBase
should technically be a set, but membership is cheaper with a RevFlag.
COMMON appears on a commit reachable from a WANT when there is also a
PEER_HAS flag present, as this is a merge base. Scrubbing this off
when another branch is tested isn't useful.
SATISIFIED is a cache to tell us if wantSatisified() has already
completed for this particular WANT. If it has, there isn't a need to
recompute on that branch. Scrubbing it off 'maint' when we test
'master' just means we would later need to re-test 'maint', wasting
CPU time on the server.
Bug: 301639
Change-Id: I3bb67d68212e4f579e8c5dfb138f007b406d775f
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
okToGiveUpImp() has been missing a ! for a long time. This loop over
wantAll() is looking for an object where wantSatisfied() returns
false, because there is no common merge base present. Unfortunately
it was missing a !, causing the loop to break and return false after
at least one want was satisified.
Bug: 301639
Change-Id: Ifdbe0b22c9cd0a9181546d090b4990d792d70c82
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
JGit did not use sh -c to run the receive-pack or upload-pack programs
locally, which caused errors if these strings contained spaces and
needed the local shell to evaluate them.
Win32 support using cmd.exe /c is completely untested, but seems like
it should work based on the limited information I could get through
Google search results.
Bug: 336301
Change-Id: I22e5e3492fdebbae092d1ce6b47ad411e57cc1ba
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
If a client wants to perform a clone of the repository, it sends
wants, but no haves. There is no point in parsing the want list
within UploadPack, as there won't be a common merge base search.
Instead just defer the parsing to PackWriter, which will do its
own parsing and object enumeration.
If the client does have a "have" set, defer parsing of the want list
until the have list is also parsed, and parse them together in a
single batch queue. This lets the underlying storage system use a
larger lookup batch if there is significant latency involved when
resolving an ObjectId to a RevObject.
Change-Id: I9c30d34f8e344da05c8a2c041a6dc181d8e8bc19
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>
It isn't strictly necessary to validate every reference's target
object is reachable in the repository before advertising it to a
client. This is an expensive operation when there are thousands of
references, and its very unlikely that a reference uses a missing
object, because garbage collection proceeds from the references and
walks down through the graph. So trying to hide a dangling reference
from clients is relatively pointless.
Even if we are trying to avoid giving a client a corrupt repository,
this simple check isn't sufficient. It is possible for a reference to
point to a valid commit, but that commit to have a missing blob in its
root tree. This can be caused by staging a file into the index,
waiting several weeks, then committing that file while also racing
against a prune. The prune may delete the blob, since its
modification time is more than 2 weeks ago, but retain the commit,
since its modification time is right now.
Such graph corruption is already caught during PackWriter as it
enumerates the graph from the client's want list and digs back
to the roots or common base. Leave the reference validation also
for that same phase, where we know we have to parse the object to
support the enumeration.
Change-Id: Iee70ead0d3ed2d2fcc980417d09d7a69b05f5c2f
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
PushCommand now does not set a null credentials provider on
Transport because in this case the default provider is replaced with
null and the default mechanism for providing credentials is not
working.
Bug: 336023
Change-Id: I7a7a9221afcfebe2e1595a5e59641e6c1ae4a207
Signed-off-by: Jens Baumgart <jens.baumgart@sap.com>
When MergeMessageFormatter was given a symbolic ref HEAD which points to
refs/heads/master (which is the case when merging a branch in EGit), it
would result in a merge message like the following:
Merge branch 'a' into HEAD
But it should print the following (as C Git does):
Merge branch 'a'
The solution is to use the leaf ref when checking for refs/heads/master.
Change-Id: I28ae5713b7e8123a0176fc6d7356e469900e7e97
There is no point in pushing all of the files within the edge
commits into the delta search when making a thin pack. This floods
the delta search window with objects that are unlikely to be useful
bases for the objects that will be written out, resulting in lower
data compression and higher transfer sizes.
Instead observe the path of a tree or blob that is being pushed
into the outgoing set, and use that path to locate up to WINDOW
ancestor versions from the edge commits. Push only those objects
into the edgeObjects set, reducing the number of objects seen by the
search window. This allows PackWriter to only look at ancestors
for the modified files, rather than all files in the project.
Limiting the search to WINDOW size makes sense, because more than
WINDOW edge objects will just skip through the window search as
none of them need to be delta compressed.
To further improve compression, sort edge objects into the front
of the window list, rather than randomly throughout. This puts
non-edges later in the window and gives them a better chance at
finding their base, since they search backwards through the window.
These changes make a significant difference in the thin-pack:
Before:
remote: Counting objects: 144190, done
remote: Finding sources: 100% (50275/50275)
remote: Getting sizes: 100% (101405/101405)
remote: Compressing objects: 100% (7587/7587)
Receiving objects: 100% (50275/50275), 24.67 MiB | 9.90 MiB/s, done.
Resolving deltas: 100% (40339/40339), completed with 2218 local objects.
real 0m30.267s
After:
remote: Counting objects: 61549, done
remote: Finding sources: 100% (50275/50275)
remote: Getting sizes: 100% (18862/18862)
remote: Compressing objects: 100% (7588/7588)
Receiving objects: 100% (50275/50275), 11.04 MiB | 3.51 MiB/s, done.
Resolving deltas: 100% (43160/43160), completed with 5014 local objects.
real 0m22.170s
The resulting pack is 13.63 MiB smaller, even though it contains the
same exact objects. 82,543 fewer objects had to have their sizes
looked up, which saved about 8s of server CPU time. 2,796 more
objects from the client were used as part of the base object set,
which contributed to the smaller transfer size.
Change-Id: Id01271950432c6960897495b09deab70e33993a9
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Sigend-off-by: Chris Aniszczyk <caniszczyk@gmail.com>
Some of this code predates making ObjectId.equals() final
and fixing RevObject.equals() to match ObjectId.equals().
It was therefore more complex than it needs to be, because
it tried to work around RevObject's broken equals() rules
by converting to ObjectId in a different collection.
Also combine setUpWalker() and findObjectsToPack() methods,
these can be one method and the code is actually cleaner.
Change-Id: I0f4cf9997cd66d8b6e7f80873979ef1439e507fe
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>
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>
When compressing objects, don't include the edges in the progress
meter. These cost almost no CPU time as they are simply pushed into
and popped out of the delta search window.
Change-Id: I7ea19f0263e463c65da34a7e92718c6db1d4a131
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>
Enhance the Git API to support cloning repositories.
Bug: 334763
Change-Id: Ibe1191498dceb9cbd1325aed85b4c403db19f41e
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>
CGit push clients 1.6.6 and later support progress messages on the
side-band-64k channel during push, as this was introduced to handle
server side hook errors reported over smart HTTP.
Since JGit's delta resolution isn't always as fast as CGit's is,
a user may think the server has crashed and failed to report
status if the user pushed a lot of content and sees no feedback.
Exposing the progress monitor during the resolving deltas phase
will let the user know the server is still making forward progress.
This also helps BasePackPushConnection, which has a bounded timeout
on how long it will wait before assuming the remote server is dead.
Progress messages pushed down the side-band channel will reset the
read timer, helping the connection to stay alive and avoid timing
out before the remote side's work is complete.
Change-Id: I429c825e5a724d2f21c66f95526d9c49edcc6ca9
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Non-commits are added to a pending queue, but duplicates are
removed by checking a flag. During a reset that flag must be
stripped off the old roots, otherwise the caller cannot reuse
the old roots after the reset.
RevWalk already does this correctly for commits, but ObjectWalk
failed to handle the non-commit case itself.
Change-Id: I99e1832bf204eac5a424fdb04f327792e8cded4a
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
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>
The new addIfAbsent() method combines get() with add(), but does
it in a single step so that the common case of get() returning null
for a new object can immediately insert the object into the map.
Change-Id: Ib599ab4de13ad67665ccfccf3ece52ba3222bcba
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
This reverts commit f5fe2dca3c.
I regret adding this feature to the public API. Caches aren't always
the best idea, as they require work to maintain. Here the cache is
redundant information that must be computed, and when it grows stale
must be removed. The redundant information takes up more disk space,
about the same size as the pack-*.idx files are. For the linux-2.6
repository, that's more than 40 MB for a 400 MB repository. So the
cache is a 10% increase in disk usage.
The entire point of this cache is to improve PackWriter performance,
and only PackWriter performance, and only when sending an initial
clone to a new client. There may be better ways to optimize this, and
until we have a solid solution, we shouldn't be using a separate cache
in JGit.
Rebase must honor the upstream configuration
branch.<branchname>.rebase
Change-Id: Ic94f263d3f47b630ad75bd5412cb4741bb1109ca
Signed-off-by: Mathias Kinzler <mathias.kinzler@sap.com>
This bug was hidden by an incomplete test: the current Rebase
implementation using the "git rebase -i" pattern does not work
correctly if fast-forwarding is involved. The reason for this is that
the log command does not return any commits in this case.
In addition, a check for already merged commits was introduced to
avoid spurious conflicts.
Change-Id: Ib9898fe0f982fa08e41f1dca9452c43de715fdb6
Signed-off-by: Mathias Kinzler <mathias.kinzler@sap.com>
IOException constructor taking Exception as parameter is
new for JDK 6.
Change-Id: Iec349fc7be9e9fbaeb53841894883c47a98a7b29
Signed-off-by: Mathias Kinzler <mathias.kinzler@sap.com>
java.io.File.mkdir() and mkdirs() report failure as an exceptional
return value false. Fix the code which silently ignored this
exceptional return value.
Change-Id: I41244f4b9d66176e68e2c07e2329cf08492f8619
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
DirCacheCheckout.checkoutEntry() prepares the new file content using a
temporary file and then renames it to the file to be written during
checkout. For files to be updated checkout() created each file before
calling checkoutEntry(). Hence renaming the temporary file always
failed which was corrected in exception handling by retrying to rename
the file after deleting the just newly created file.
Change-Id: I219f864f2ed8d68051d7b5955d0659964fa27274
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Counting the objects needed for packing is the most expensive part of
an UploadPack request that has no uninteresting objects (otherwise
known as an initial clone). During this phase the PackWriter is
enumerating the entire set of objects in this repository, so they can
be sent to the client for their new clone.
Allow the ObjectReader (and therefore the underlying storage system)
to keep a cached list of all reachable objects from a small number of
points in the project's history. If one of those points is reached
during enumeration of the commit graph, most objects are obtained from
the cached list instead of direct traversal.
PackWriter uses the list by discarding the current object lists and
restarting a traversal from all refs but marking the object list name
as uninteresting. This allows PackWriter to enumerate all objects
that are more recent than the list creation, or that were on side
branches that the list does not include.
However, ObjectWalk tags all of the trees and commits within the list
commit as UNINTERESTING, which would normally cause PackWriter to
construct a thin pack that excludes these objects. To avoid that,
addObject() was refactored to allow this list-based enumeration to
always include an object, even if it has been tagged UNINTERESTING by
the ObjectWalk. This implies the list-based enumeration may only be
used for initial clones, where all objects are being sent.
The UNINTERESTING labeling occurs because StartGenerator always
enables the BoundaryGenerator if the walker is an ObjectWalk and a
commit was marked UNINTERESTING, even if RevSort.BOUNDARY was not
enabled. This is the default reasonable behavior for an ObjectWalk,
but isn't desired here in PackWriter with the list-based enumeration.
Rather than trying to change all of this behavior, PackWriter works
around it.
Because the list name commit's immediate files and trees were all
enumerated before the list enumeration itself starts (and are also
within the list itself) PackWriter runs the risk of adding the same
objects to its ObjectIdSubclassMap twice. Since this breaks the
internal map data structure (and also may cause the object to transmit
twice), PackWriter needs to use a new "added" RevFlag to track whether
or not an object has been put into the outgoing list yet.
Change-Id: Ie99ed4d969a6bb20cc2528ac6b8fb91043cee071
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
It can be very handy for the implementation to resort the
object list based on data locality, improving prefetch in
the operating system's buffer cache.
Export the list to the implementation was a proper List,
and document that its mutable and OK to be modified. The
only caller in PackWriter is already OK with these rules.
Change-Id: I3f51cf4388898917b2be36670587a5aee902ff10
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
When performing an initial clone of a repository there are no
uninteresting commits, and the resulting pack will be completely
self-contained. Therefore PackWriter does not need to honor C
Git standard TOPO ordering as described in JGit commit ba984ba2e0
("Fix checkReferencedIsReachable to use correct base list").
Switching to COMMIT_TIME_DESC when there are no uninteresting commits
allows the "Counting objects" phase to emit progress earlier, as the
RevWalk will not buffer the commit list. When TOPO is set the RevWalk
enumerates all commits first, before outputing any for PackWriter to
mark progress updates from.
Change-Id: If2b6a9903b536c7fb3c45f85d0a67ff6c6e66f22
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
These two methods are specific to the FileRepository implementation
and should not be exposed as part of the base Repository API. Now
that PackParser is generic and does not require these two methods
to import a pack stream into a repostiory, it is safe to remove
these and get them out of the public view.
Change-Id: I8990004d08074657f467849dabfdaa7e6674e69a
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
This problem surfaced since EGit Core ResetOperationTest is failing
since change I26806d21. JGit detected checkout conflict for untracked
files which never were tracked by the repository.
"git reset --hard" in c git also doesn't remove such untracked files.
Change-Id: Icc8e1c548ecf6ed48bd2979c81eeb6f578d347bd
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
This information is generally useful - have followed the
accessor pattern of 'children' and 'parents'
Change-Id: I79b3ddd6f390152aa49e6b7a4c72a4aca0d6bc72
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>
The change Ie0350e032a97e0d09626d6143c5c692873a5f6a2 was not
done properly. The renamed file was not write protected, and
this broke a test.
Bug: 335388
Change-Id: I41b2235b7677bc5fddc70dda2a56cdd2cb53ce5d
Signed-off-by: Robin Rosenberg <robin.rosenberg@dewire.com>
This is needed for implementing Fetch in EGit using the API.
Change-Id: Ibdcc95906ef0f93e3798ae20d4de353fb394f2e2
Signed-off-by: Mathias Kinzler <mathias.kinzler@sap.com>
When DirCacheCheckout was checking out it was silently
overwriting untracked files. This is only ok if the
files are also ignored. Untracked and not ignored files
should not be overwritten. This fix adds checks for
this situation.
Because this change in the behaviour also broke tests
which expected that a checkout will overwrite untracked
files (PullCommandTest) these tests have to be modified
also.
Bug: 333093
Change-Id: I26806d2108ceb64c51abaa877e11b584bf527fc9
Signed-off-by: Christian Halstrick <christian.halstrick@sap.com>
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>
We cannot always rename read-only files on network shares,
so rename the temp file for a new loose object first, and
then set it as read-only.
Bug: 335388
Change-Id: Ie0350e032a97e0d09626d6143c5c692873a5f6a2
Signed-off-by: Robin Rosenberg <robin.rosenberg@dewire.com>
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>