Convert documentation to markdown.

Markdown is more readable in a text editor and when hosted
on GitHub is more readable than HTML.

-------------
Created by MOE: https://github.com/google/moe
MOE_M

Convert documentation to markdown.

Markdown is more readable in a text editor and when hosted
on GitHub is more readable than HTML.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=148830423

show more ...

Add option for max file size. The currend hard-coded value of 2M is inefficient in colossus.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=134391640

Change std::uint64_t to uint64_t (#354)

-This fixes compile errors with default setup on RHEL 6 systems.

This CL fixes a bug encountered when reading records from leveldb files that have been split, as in a [] input task split.

Detailed description:

Suppose an input split is generated between two leve

This CL fixes a bug encountered when reading records from leveldb files that have been split, as in a [] input task split.

Detailed description:

Suppose an input split is generated between two leveldb record blocks and the preceding block ends with null padding.

A reader that previously read at least 1 record within the first block (before encountering the padding) upon trying to read the next record, will successfully and correctly read the next logical record from the subsequent block, but will return a last record offset pointing to the padding in the first block.

When this happened in a [], it resulted in duplicate records being handled at what appeared to be different offsets that were separated by only a few bytes.

This behavior is only observed when at least 1 record was read from the first block before encountering the padding. If the initial offset for a reader was within the padding, the correct record offset would be reported, namely the offset within the second block.

The tests failed to catch this scenario/bug, because each read test only read a single record with an initial offset. This CL adds an explicit test case for this scenario, and modifies the test structure to read all remaining records in the test case after an initial offset is specified. Thus an initial offset that jumps to record #3, with 5 total records in the test file, will result in reading 2 records, and validating the offset of each of them in order to pass successfully.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=115338487

show more ...

Fix signed/unsigned mismatch on VC++ builds

Putting build artifacts in subdirectory.

1. Object files, libraries, and compiled executables are put
into subdirectories.
2. The shared library is linked from individual object files.
This pr

Putting build artifacts in subdirectory.

1. Object files, libraries, and compiled executables are put
into subdirectories.
2. The shared library is linked from individual object files.
This provides for greater parallelism on large desktops
while at the same time making for easier builds on small
(i.e. embedded) systems. Fixes issue #279.
3. One program, db_bench, is compiled using the shared library.
4. The source file for "leveldbutil" was renamed from
leveldb_main.cc to leveldbutil.cc. This provides for simpler
makefile rules.
5. Because all targets placed the library (libleveldb.a) at the top
level, the last platform built (desktop/device) always overwrote
any prior artifact.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=113407013

show more ...

Resolve race when getting approximate-memory-usage property

The write operations in the table happens without holding the mutex
lock, but concurrent writes are avoided using "writers_" queue.
The Ar

Resolve race when getting approximate-memory-usage property

The write operations in the table happens without holding the mutex
lock, but concurrent writes are avoided using "writers_" queue.
The Arena::MemoryUsage could access the blocks when write happens.
So, the memory usage is cached in atomic word and can be loaded
from any thread safely.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=107573379

show more ...

Only compiling TrimSpace on linux.

Incorporated change by zmodem at https://github.com/google/leveldb/pull/310
to fix issue #310.

This change will only build TrimSace on linux to avoid unused funct

Only compiling TrimSpace on linux.

Incorporated change by zmodem at https://github.com/google/leveldb/pull/310
to fix issue #310.

This change will only build TrimSace on linux to avoid unused function
warning/error.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=105323419

show more ...

Add "approximate-memory-usage" property to leveldb::DB::GetProperty

The approximate RAM usage of the database is calculated from the memory
allocated for write buffers and the block cache. This is t

Add "approximate-memory-usage" property to leveldb::DB::GetProperty

The approximate RAM usage of the database is calculated from the memory
allocated for write buffers and the block cache. This is to give an
estimate of memory usage to leveldb clients.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=104222307

show more ...

Suppress error reporting after seeking but before a valid First or Full record is encountered.

Fix a spelling mistake.

Will not reuse manifest if reuse_logs options is false.

Prior implementation would always try to reuse the manifest, even if reuse_logs
was false (the default). This was missed because the stock
Env

Will not reuse manifest if reuse_logs options is false.

Prior implementation would always try to reuse the manifest, even if reuse_logs
was false (the default). This was missed because the stock
Env::NewAppendableFile implementation returns false forcing the creation of a
new log.

show more ...

LevelDB now attempts to reuse the preceding MANIFEST and log file when re-opened.

(Based on a suggestion by cmumford.)

"open" benchmark on my workstation speeds up significantly since we
can now av

LevelDB now attempts to reuse the preceding MANIFEST and log file when re-opened.

(Based on a suggestion by cmumford.)

"open" benchmark on my workstation speeds up significantly since we
can now avoid three fdatasync calls and a compaction per open:

Before: ~80000 microseconds
After: ~130 microseconds

Details:

(1) Added Options::reuse_logs (currently defaults to false) to control
new behavior. The intention is to change the default to true after some
baking.

(2) Added Env::NewAppendableFile() whose default implementation returns
a not-supported error.

(3) VersionSet::Recovery attempts to reuse the MANIFEST from which
it is recovering.

(4) DBImpl recovery attempts to reuse the last log file and memtable.

(5) db_test.cc now tests a new configuration that sets reuse_logs to true.

(6) fault_injection_test also tests a reuse_logs==true config.

(7) Added a new recovery_test.

show more ...

fix indent

log compaction output file's level along with number

Add benchmark that measures cost of repeatedly opening the database.

Move header guard below copyright banner.

Clean up layering of storage/leveldb/...

With these changes, this package should be properly cleaned up and not require
any further changes.

Added a new fault injection test.

This test is intended to ensure leveldb properly detects and recovers from
faults - specifically unwritten file data lost as a result of a system reset.

Release 1.18

Changes are:

* Update version number to 1.18
* Replace the basic fprintf call with a call to fwrite in order to
work around the apparent compiler optimization/rewrite failure that we

Release 1.18

Changes are:

* Update version number to 1.18
* Replace the basic fprintf call with a call to fwrite in order to
work around the apparent compiler optimization/rewrite failure that we are
seeing with the new toolchain/iOS SDKs provided with Xcode6 and iOS8.
* Fix ALL the header guards.
* Createed a README.md with the LevelDB project description.
* A new CONTRIBUTING file.
* Don't implicitly convert uint64_t to size_t or int. Either preserve it as
uint64_t, or explicitly cast. This fixes MSVC warnings about possible value
truncation when compiling this code in Chromium.
* Added a DumpFile() library function that encapsulates the guts of the
"leveldbutil dump" command. This will allow clients to dump
data to their log files instead of stdout. It will also allow clients to
supply their own environment.
* leveldb: Remove unused function 'ConsumeChar'.
* leveldbutil: Remove unused member variables from WriteBatchItemPrinter.
* OpenBSD, NetBSD and DragonflyBSD have _LITTLE_ENDIAN, so define
PLATFORM_IS_LITTLE_ENDIAN like on FreeBSD. This fixes:
* issue #143
* issue #198
* issue #249
* Switch from <cstdatomic> to <atomic>. The former never made it into the
standard and doesn't exist in modern gcc versions at all. The later contains
everything that leveldb was using from the former.
This problem was noticed when porting to Portable Native Client where no memory
barrier is defined. The fact that <cstdatomic> is missing normally goes
unnoticed since memory barriers are defined for most architectures.
* Make Hash() treat its input as unsigned. Before this change LevelDB files
from platforms with different signedness of char were not compatible. This
change fixes: issue #243
* Verify checksums of index/meta/filter blocks when paranoid_checks set.
* Invoke all tools for iOS with xcrun. (This was causing problems with the new
XCode 5.1.1 image on pulse.)
* include <sys/stat.h> only once, and fix the following linter warning:
"Found C system header after C++ system header"
* When encountering a corrupted table file, return Status::Corruption instead of
Status::InvalidArgument.
* Support cygwin as build platform, patch is from https://code.google.com/p/leveldb/issues/detail?id=188
* Fix typo, merge patch from https://code.google.com/p/leveldb/issues/detail?id=159
* Fix typos and comments, and address the following two issues:
* issue #166
* issue #241
* Add missing db synchronize after "fillseq" in the benchmark.
* Removed unused variable in SeekRandom: value (issue #201)

show more ...

Release LevelDB 1.17

- Cleanup: delete unused IntSetToString

It was added in http://cr/19491949 (and was referenced at the time).
The last reference was removed in http://cr/19507363.

This f

Release LevelDB 1.17

- Cleanup: delete unused IntSetToString

It was added in http://cr/19491949 (and was referenced at the time).
The last reference was removed in http://cr/19507363.

This fixes warning/error with pre-release crosstoolv18:
'std::string leveldb::{anonymous}::IntSetToString(const std::set<long unsigned int>&)' defined but not used [-Werror=unused-function]

- Added arm64 and and armv7s to IOS build as suggested on leveldb mailing list.

- Changed local variable type from int to size_t

This eliminates compiler warning/error and resolves
https://code.google.com/p/leveldb/issues/detail?id=140

show more ...

Release LevelDB 1.16

- Make Log::Reader not report a corruption when the last record in a
log file is truncated.
- Fix issue 224: variable created but not utilized.
- Remove comment that reference

Release LevelDB 1.16

- Make Log::Reader not report a corruption when the last record in a
log file is truncated.
- Fix issue 224: variable created but not utilized.
- Remove comment that referenced a removed feature.

show more ...

Release LevelDB 1.15

- switched from mmap based writing to simpler stdio based writing. Has a
minor impact (0.5 microseconds) on microbenchmarks for asynchronous
writes. Synchronous writes speed

Release LevelDB 1.15

- switched from mmap based writing to simpler stdio based writing. Has a
minor impact (0.5 microseconds) on microbenchmarks for asynchronous
writes. Synchronous writes speed up from 30ms to 10ms on linux/ext4.
Should be much more reliable on diverse platforms.
- compaction errors now immediately put the database into a read-only
mode (until it is re-opened). As a downside, a disk going out of
space and then space being created will require a re-open to recover
from, whereas previously that would happen automatically. On the
plus side, many corruption possibilities go away.
- force the DB to enter an error-state so that all future writes fail
when a synchronous log write succeeds but the sync fails.
- repair now regenerates sstables that exhibit problems
- fix issue 218 - Use native memory barriers on OSX
- fix issue 212 - QNX build is broken
- fix build on iOS with xcode 5
- make tests compile and pass on windows

show more ...

Release LevelDB 1.14

Fix issues 200, 201

Also,
* Fix link to bigtable paper in docs.
* New sstables will have the file extension .ldb. .sst files will
continue to be recognized.
* When building for

Release LevelDB 1.14

Fix issues 200, 201

Also,
* Fix link to bigtable paper in docs.
* New sstables will have the file extension .ldb. .sst files will
continue to be recognized.
* When building for iOS, use xcrun to execute the compiler. This may
affect issue 177.

show more ...

LevelDB 1.13

Fix issues 77, 87, 182, 190.

Additionally, fix the bug described in
https://groups.google.com/d/msg/leveldb/yL6h1mAOc20/vLU64RylIdMJ
where a large contiguous keyspace of deleted data w

LevelDB 1.13

Fix issues 77, 87, 182, 190.

Additionally, fix the bug described in
https://groups.google.com/d/msg/leveldb/yL6h1mAOc20/vLU64RylIdMJ
where a large contiguous keyspace of deleted data was not getting
compacted.

Also fix a bug where options.max_open_files was not getting clamped
properly.

show more ...

Release leveldb 1.11

Fixes issues
161
174
178

As well as the issue reported by [email protected] about
MissingSSTFile unit test failing on windows.