Parsing the size from a packed object header was incorrectly computing
the total inflated length when the length exceeded the range of a Java
int. The next 7 bits of size information was shifted left as an int
using a shift of 25 bits, placing the higher bits of the size into the
sign position. When this size was extended to a long to be added to
the current size accumulator the size went negative, resulting in
NegativeArraySizeException being thrown.
Fix all places where this particular pattern of code is used to read a
pack size field, or a binary delta header, as they both use the same
variable length encoding scheme.
Change-Id: I04008728ed828f18202652c3d5401cf95a441d0a
Enforce the use of Java5 API:s only (with a few exceptions)
This only works with Eclipse 3.6 and newer and requires installation
of new package. Documentation is not very good, but there is a blog
about it here:
http://eclipseandjazz.blogspot.com/2011/10/of-invalid-references-to-system.html
API checking is especially useful on OS X where Java5 is not readily
available.
Change-Id: I3c0ad460874a21c073f5ac047146cbf5d31992b4
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
In order to generate API reports run: mvn clirr:clirr
The reports are generated to the folder
target/site/clirr-report.html under the respective
project.
In order to check API compatibility and fail the build
on incompatible changes run: mvn clirr:check
For now we compare the API against the latest release
1.1.0.201109151100-r.
Bug: 336849
Change-Id: I21baaf3a6883c5b4db263f712705cc7b8ab6d888
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Signed-off-by: Kevin Sawicki <kevin@github.com>
Since we replaced GitIndex by DirCache JGit didn't fire
IndexChangedEvents anymore. For EGit this still worked with a high
latency since its RepositoryChangeScanner which is scheduled to
run each 10 seconds fires the event in case the index changes.
This scanner is meant to detect index changes induced by a different
process e.g. by calling "git add" from native git.
When the index is changed from within the same process we should fire
the event synchronously. Compare the index checksum on write to index
checksum when index was read earlier to determine if index really
changed. Use IndexChangedListener interface to keep DirCache decoupled
from Repository.
Change-Id: Id4311f7a7859ffe8738863b3d86c83c8b5f513af
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
Use commit message best practices for Mylyn Commit template
We should use a template for Mylyn commit messages that matches with our
guidelines for commit messages.
http://wiki.eclipse.org/EGit/Contributor_Guide#Commit_message_guidelines
Bug: 337401
Change-Id: I05812abf0eb0651d22c439142640f173fc2f2ba0
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
This is required since RefList.put returns a new RefList.
Change-Id: I717d75d6f6154a6e0dc7cde3b72b0a59c68d955c
Signed-off-by: Kevin Sawicki <kevin@github.com>
DHT: Change DhtReadher caches to be dynamic by workload
Instead of fixing the prefetch queue and recent chunk queue as
different sizes, allow these to share the same limit but be scaled
based on the work being performed.
During walks about 20% of the space will be given to the prefetcher,
and the other 80% will be used by the recent chunks cache. This
should improve cases where there is bad locality between chunks.
During writing of a pack stream, 90-100% of the space should be
made available to the prefetcher, as the prefetch plan is usually
very accurate about the order chunks will be needed in.
Change-Id: I1ca7acb4518e66eb9d4138fb753df38e7254704d
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
A linear search is somewhat acceptable for only 4 recent chunks, but
a HashMap based lookup would be better. The table will have 16 slots
by default and given the hashCode() of ChunkKey is derived from the
SHA-1 of the chunk, each chunk will fall into its own bucket within
the table and thus evaluate only 1 entry during lookup instead of 4.
Some users may also want to devote more memory to the recent chunks,
in which case expanding this list to a longer length will help to
reduce chunk faults, but would increase search time. Using a HashMap
will help this code to scale to larger sizes better.
Change-Id: Ia41b7a1cc69ad27b85749e3b74cbf8d0aa338044
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
DHT: Always have at least one recent chunk in DhtReader
The RecentChunks cache assumes there is always at least one recent
chunk in the maxSize that it receives from the DhtReaderOptions.
Ensure that is true by requiring the size to be at least 1.
Running with 0 recent chunk cache is very a bad idea, often
during commit walking the parents of a commit will be found
on the same chunk as the commit that was just accessed. In
these cases its a good idea to keep that last chunk around
so the parents can be quickly accessed.
Change-Id: I33b65286e8a4cbf6ef4ced28c547837f173e065d
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
The Prefetcher may have loaded a chunk that is a fragment, if the
DhtReader is scanning the Prefetcher's chunks for a particular
object fragment chunks will be missing the index and NPE during
the findOffset() call into the index itself.
Change-Id: Ie2823724c289f745655076c5209acec32361a1ea
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Originally I put the first two digits of the object SHA-1 into the
start of a row key to try and spread the load of objects around a DHT
service. Unfortunately this tends to not work as well as I had hoped.
Servers reading a repository need to contact every node in a DHT
cluster if the cluster tries to evenly distribute the object rows.
This is a lot of connections, especially if the cluster has many
backend storage servers. If the library has an open connection
limit (possibly due to JVM file descriptor limitations) it may need
to open and close a lot of connections to access a repository,
rather than being able to reuse the same connection to a handful
of backend servers. This results in a lot of connection thrashing
for some DHT type databases, and is inefficient.
Some DHTs are able to operate even if part of the database space
is currently unavailable. For example, a DHT service might assign
some section of the key space to a node, and then fail that section
over to another node when the primary is noticed as being offline.
During that failover period that section of the key space is not
available, but other sections hosted by other backends are still
ready for service. Spreading keys all over the cluster makes it
likely that any single backend being temporarily down means the
entire cluster is down, rather than only some.
This is a massive schema change, but it should improve relability
and performance for any DHT system.
Change-Id: I6b65bfb4c14b6f7bd323c2bd0638b49d429245be
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
The first step to deleting a repository from the DHT storage is to
remove the name binding in the RepositoryIndexTable, making the
repository unavailable for lookup.
Change-Id: I469bf92f4bf2f555a15949569b21937c14cb142b
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
DHT: Fix thread-safety issue in AbstractWriteBuffer
There is a data corruption issue with the 'running' list if a
background thread schedules something onto the buffer while the
application thread is also using it.
Change-Id: I5ba78b98b6632965d677a9c8f209f0cf8320cc3d
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
RefData now uses a sequence number as part of the field, ensuring
that updates always increase the sequence number by one whenever
a reference is modified.
Attaching a sequence number to RefData will help with storing
reference log entries during updates. As the sequence number should
be unique within the reference name space, log entries can be keyed
by the sequence number and remain unique. Making this work over
reference delete-create cycles will require an additional RefTable
API to return the oldest sequence number previously used in the
reference log to seed the recreated reference.
Change-Id: I11cfff2a96ef962e57f29925a3eef41bdbf9f9bb
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>
Matthias Sohn
Robin Rosenberg
Shawn O. Pearce
Kevin Sawicki