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* Stop future writes if a log file Close() fails.Sanjay Ghemawat2023-01-041-0/+14
| | | | | | See https://github.com/google/leveldb/issues/1081 PiperOrigin-RevId: 499519182
* Sync MANIFEST before closing in db_impl when creating a new DB.leveldb Team2021-01-121-0/+5
| | | | | | Add logging with debugging information when failing to load a version set. PiperOrigin-RevId: 351432332
* Add some std:: qualifiers to types and functions.Victor Costan2020-04-291-15/+15
| | | | PiperOrigin-RevId: 309110431
* Switch from C headers to C++ headers.Victor Costan2020-04-291-3/+2
| | | | | | | | | | | | | | | This CL makes the following substitutions. * assert.h -> cassert * math.h -> cmath * stdarg.h -> cstdarg * stddef.h -> cstddef * stdint.h -> cstdint * stdio.h -> cstdio * stdlib.h -> cstdlib * string.h -> cstring PiperOrigin-RevId: 309080151
* Add Env::Remove{File,Dir} which obsolete Env::Delete{File,Dir}.Victor Costan2020-01-091-10/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The "DeleteFile" method name causes pain for Windows developers, because <windows.h> #defines a DeleteFile macro to DeleteFileW or DeleteFileA. Current code uses workarounds, like #undefining DeleteFile everywhere an Env is declared, implemented, or used. This CL removes the need for workarounds by renaming Env::DeleteFile to Env::RemoveFile. For consistency, Env::DeleteDir is also renamed to Env::RemoveDir. A few internal methods are also renamed for consistency. Software that supports Windows is expected to migrate any Env implementations and usage to Remove{File,Dir}, and never use the name Env::Delete{File,Dir} in its code. The renaming is done in a backwards-compatible way, at the risk of making it slightly more difficult to build a new correct Env implementation. The backwards compatibility is achieved using the following hacks: 1) Env::Remove{File,Dir} methods are added, with a default implementation that calls into Env::Delete{File,Dir}. This makes old Env implementations compatible with code that calls into the updated API. 2) The Env::Delete{File,Dir} methods are no longer pure virtuals. Instead, they gain a default implementation that calls into Env::Remove{File,Dir}. This makes updated Env implementations compatible with code that calls into the old API. The cost of this approach is that it's possible to write an Env without overriding either Rename{File,Dir} or Delete{File,Dir}, without getting a compiler warning. However, attempting to run the test suite will immediately fail with an infinite call stack ending in {Remove,Delete}{File,Dir}, making developers aware of the problem. PiperOrigin-RevId: 288710907
* Renamed local variable in DBImpl::Write.Chris Mumford2019-10-281-6/+6
| | | | | | | The local variable `updates` in DBImpl::Write was hiding the `updates` parameter. Renamed to avoid this conflict. PiperOrigin-RevId: 277089971
* Simplify unlocking in DeleteObsoleteFiles.Chris Mumford2019-06-131-12/+15
| | | | | | | | | | | | | | | | A recent change (4cb80b7ddce6f) to DBImpl::DeleteObsoleteFiles unlocked DBImpl::mutex_ while deleting files to allow for greater concurrency. This change improves on the prior in a few areas: 1. The table is evicted from the table cache before unlocking the mutex. This should only improve performance. 2. This implementation is slightly simpler, but at the cost of a bit more memory usage. 3. A comment adding more detail as to why the mutex is being unlocked and why it is safe to do so. PiperOrigin-RevId: 253111645
* Merge pull request #386 from ivanabc:masterChris Mumford2019-05-301-3/+10
|\ | | | | | | PiperOrigin-RevId: 250702492
| * Merge branch 'master' into masterivan2019-05-231-325/+354
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| * set const propertyivanabc2016-06-211-3/+5
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| * reduce lock's range in DeleteObsoleteFilesivanabc2016-06-201-3/+12
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* | Guard DBImpl::versions_ by mutex_.Chris Mumford2019-05-161-11/+6
| | | | | | | | | | | | | | | | mutex_ was already acquired before accessing DBImpl::versions_ in all but one place: DBImpl::GetApproximateSizes. This change requires mutex_ to be held before accessing versions_. PiperOrigin-RevId: 248390814
* | Converted two for-loops to while-loops.Chris Mumford2019-05-131-1/+1
| | | | | | | | | | | | Converted `for (;<condition>;)` to `while (<condition>)`. PiperOrigin-RevId: 247950510
* | Switch to using C++ 11 override specifier.Chris Mumford2019-05-091-1/+1
| | | | | | | | PiperOrigin-RevId: 247491163
* | Style cleanup.Victor Costan2019-05-041-2/+2
| | | | | | | | | | | | | | | | | | 1) Convert iterator-based for loops to C++11 foreach loops. 2) Convert "void operator=" to "T& operator=". 3) Switch from copy operators from private to public deleted. 4) Switch from empty ctors / dtors to "= default" where appropriate. PiperOrigin-RevId: 246679195
* | Correct class/structure declaration order.Chris Mumford2019-05-031-18/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | 1. Correct the class/struct declaration order to be IAW the Google C++ style guide[1]. 2. For non-copyable classes, switched from non-implemented private methods to explicitly deleted[2] methods. 3. Minor const and member initialization fixes. [1] https://google.github.io/styleguide/cppguide.html#Declaration_Order [2] http://eel.is/c++draft/dcl.fct.def.delete PiperOrigin-RevId: 246521844
* | Format all files IAW the Google C++ Style Guide.Chris Mumford2019-05-021-105/+74
| | | | | | | | | | | | Use clang-format to correct formatting to be in agreement with the [Google C++ Style Guide](https://google.github.io/styleguide/cppguide.html). Doing this simplifies the process of accepting changes. Also fixed a few warnings flagged by clang-tidy. PiperOrigin-RevId: 246350737
* | Initialize class members to default values in constructors.Chris Mumford2019-04-121-3/+4
| | | | | | | | | | | | | | | | | | | | There were a few members which were identified to have been left uninitialized in some constructors. These were very likely to have been set before being used, otherwise the ASan tests would have caught them, but still good practice to have them initialized. This addresses some items reported in issue #668. PiperOrigin-RevId: 243370145
* | leveldb: Replace AtomicPointer with std::atomic.costan2019-03-111-16/+17
| | | | | | | | | | | | | | | | | | | | | | | | This CL removes AtomicPointer from leveldb's port interface. Its usage is replaced with std::atomic<> from the C++11 standard library. AtomicPointer was used to wrap flags, numbers, and pointers, so its instances are replaced with std::atomic<bool>, std::atomic<int>, std::atomic<size_t> and std::atomic<Node*>. This CL does not revise the memory ordering. AtomicPointer's methods are replaced mechanically with their std::atomic equivalents, even when the underlying usage is incorrect. (Example: DBImpl::has_imm_ is written using release stores, even though it is always read using relaxed ordering.) Revising the memory ordering is left for future CLs. ------------- Created by MOE: https://github.com/google/moe MOE_MIGRATED_REVID=237865146
* | Clean up SnapshotImpl.costan2018-04-301-5/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | * Omit SnapshotImpl::list_ when assert() isn't on * Make SnapshotImpl::number_ const and set it in the constructor * Make SnapshotImpl::number_ private and access it via a getter * Rename SnapshotImpl::number_ to SnapshotImpl::sequence_number_ * Rename SnapshotList::list_ to SnapshotList::head_ * Wrap casting from Snapshot* to SnapshotImpl* in ToSnapshotImpl() ------------- Created by MOE: https://github.com/google/moe MOE_MIGRATED_REVID=194852828
* | Replace NULL with nullptr in C++ files.costan2018-04-101-92/+92
| | | | | | | | | | | | ------------- Created by MOE: https://github.com/google/moe MOE_MIGRATED_REVID=192365747
* | leveldb: Add more thread safety annotations.costan2018-03-231-10/+11
| | | | | | | | | | | | | | | | After this CL, all classes with Mutex members should be covered by annotations. Exceptions are atomic members, which shouldn't need locking, and DBImpl members that cause errors when annotated, which will be tackled separately. ------------- Created by MOE: https://github.com/google/moe MOE_MIGRATED_REVID=190260865
* | Extend thread safety annotations.costan2018-03-161-30/+38
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This CL makes it easier to reason about thread safety by: 1) Adding Clang thread safety annotations according to comments. 2) Expanding a couple of variable names, without adding extra lines of code. 3) Adding const in a couple of places. 4) Replacing an always-non-null const pointer with a reference. 5) Fixing style warnings in the modified files. This CL does not annotate the DBImpl members that claim to be protected by the instance mutex, but are accessed without the mutex being held. Those members (and their unprotected accesses) will be addressed in future CLs. ------------- Created by MOE: https://github.com/google/moe MOE_MIGRATED_REVID=189354657
* | leveldb::DestroyDB will now delete empty directories.cmumford2017-11-031-4/+4
| | | | | | | | | | | | | | | | | | | | Env's that filtered out dot files ("." and "..") would return an empty vector of children causing DestroyDB to do nothing. This fixes https://github.com/google/leveldb/issues/215 ------------- Created by MOE: https://github.com/google/moe MOE_MIGRATED_REVID=172501335
* | Add option for max file size. The currend hard-coded value of 2M is ↵corrado2016-09-281-0/+1
| | | | | | | | | | | | | | | | inefficient in colossus. ------------- Created by MOE: https://github.com/google/moe MOE_MIGRATED_REVID=134391640
* | Merge pull request #284 from ideawu/masterChris Mumford2016-01-121-1/+2
|\ \ | | | | | | log compaction output file's level along with number
| * | fix indentideawu2015-04-201-1/+1
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| * | log compaction output file's level along with numberideawu2015-04-201-1/+2
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* | Add "approximate-memory-usage" property to leveldb::DB::GetPropertyssid2015-12-091-0/+13
| | | | | | | | | | | | | | | | | | 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
* | LevelDB now attempts to reuse the preceding MANIFEST and log file when ↵Sanjay Ghemawat2015-08-111-69/+109
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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.
* Release 1.18v1.18Chris Mumford2014-09-161-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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)
* Release LevelDB 1.15v1.15David Grogan2013-12-101-42/+57
| | | | | | | | | | | | | | | | | | | - 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
* LevelDB 1.13v1.13David Grogan2013-08-211-14/+27
| | | | | | | | | | | | 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.
* Release leveldb 1.11v1.11David Grogan2013-06-131-6/+15
| | | | | | | | | | Fixes issues 161 174 178 As well as the issue reported by edouarda14@gmail.com about MissingSSTFile unit test failing on windows.
* Release leveldb 1.10v1.10David Grogan2013-05-141-1/+2
| | | | | | | | | | | | | | | Fixes issues 147 - thanks feniksgordonfreeman 153 156 166 Additionally, * Remove calls to exit(1). * Fix unused-variable warnings from clang. * Fix possible overflow error related to num_restart value >= (2^32/4). * Add leveldbutil to .gitignore. * Add better log messages when Write is stalled on a compaction.
* Make DB::Open fail if sst files are missing.David Grogan2013-02-061-4/+12
| | | | Also, cleanup for Clang's -Wimplicit-fallthrough warning.
* Update to leveldb 1.6v1.6David Grogan2012-10-121-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Highlights ---------- Mmap at most 1000 files on Posix to improve performance for large databases. Support for more architectures (thanks to Alexander K.) Building and porting -------------------- HP/UX support (issue 126) AtomicPointer for ia64 (issue 123) Sparc v9 support (issue 124) Atomic ops for powerpc Use -fno-builtin-memcmp only when using g++ Simplify IOS build rules (issue 114) Use CXXFLAGS instead of CFLAGS when invoking C++ compiler (issue 118) Fix snappy shared library problem (issue 94) Fix shared library installation path regression Endian-ness detection tweak for FreeBSD Bug fixes --------- Stop ignoring FLAGS_open_files in db_bench Make bloom test behavior agnostic to endian-ness Performance ----------- Limit number of mmapped files to 1000 to improve perf for large dbs Do not delay for 1 second on shutdown path (issue 125) Misc ---- Make InMemoryEnv return a no-op logger C binding now has a wrapper for free (issue 117) Add thread-safety annotations Added an in-process lock table (issue 120) Make RandomAccessFile and SequentialFile non-copyable
* Remove static initializer; fix endian-ness detection; fix build onSanjay Ghemawat2012-05-301-4/+19
| | | | | | | | | | | | | | | | | | | | | | various platforms; improve android port speed. Avoid static initializer by using a new portability interface for thread-safe lazy initialization. Custom ports will need to be extended to implement InitOnce/OnceType/LEVELDB_ONCE_INIT. Fix endian-ness detection (fixes Powerpc builds). Build related fixes: - Support platforms that have unversioned shared libraries. - Fix IOS build rules. Android improvements - Speed up atomic pointers - Share more code with port_posix. Do not spin in a tight loop attempting compactions if the file system is inaccessible (e.g., if kerberos tickets have expired or if it is out of space).
* Added bloom filter support.v1.4Sanjay Ghemawat2012-04-171-4/+8
| | | | | | | | | | | | | | | | | | | | In particular, we add a new FilterPolicy class. An instance of this class can be supplied in Options when opening a database. If supplied, the instance is used to generate summaries of keys (e.g., a bloom filter) which are placed in sstables. These summaries are consulted by DB::Get() so we can avoid reading sstable blocks that are guaranteed to not contain the key we are looking for. This change provides one implementation of FilterPolicy based on bloom filters. Other changes: - Updated version number to 1.4. - Some build tweaks. - C binding for CompactRange. - A few more benchmarks: deleteseq, deleterandom, readmissing, seekrandom. - Minor .gitignore update.
* fix LOCK file deletion to prevent crash on windowsSanjay Ghemawat2012-03-091-1/+1
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* added group commit; drastically speeds up mult-threaded synchronous write ↵Sanjay Ghemawat2012-03-081-36/+107
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* fixed issues 66 (leaking files on disk error) and 68 (no sync of CURRENT file)Sanjay Ghemawat2012-01-251-14/+6
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* A number of fixes:Hans Wennborg2011-10-311-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Replace raw slice comparison with a call to user comparator. Added test for custom comparators. - Fix end of namespace comments. - Fixed bug in picking inputs for a level-0 compaction. When finding overlapping files, the covered range may expand as files are added to the input set. We now correctly expand the range when this happens instead of continuing to use the old range. For example, suppose L0 contains files with the following ranges: F1: a .. d F2: c .. g F3: f .. j and the initial compaction target is F3. We used to search for range f..j which yielded {F2,F3}. However we now expand the range as soon as another file is added. In this case, when F2 is added, we expand the range to c..j and restart the search. That picks up file F1 as well. This change fixes a bug related to deleted keys showing up incorrectly after a compaction as described in Issue 44. (Sync with upstream @25072954)
* A number of bugfixes:Gabor Cselle2011-10-051-30/+68
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Added DB::CompactRange() method. Changed manual compaction code so it breaks up compactions of big ranges into smaller compactions. Changed the code that pushes the output of memtable compactions to higher levels to obey the grandparent constraint: i.e., we must never have a single file in level L that overlaps too much data in level L+1 (to avoid very expensive L-1 compactions). Added code to pretty-print internal keys. - Fixed bug where we would not detect overlap with files in level-0 because we were incorrectly using binary search on an array of files with overlapping ranges. Added "leveldb.sstables" property that can be used to dump all of the sstables and ranges that make up the db state. - Removing post_write_snapshot support. Email to leveldb mailing list brought up no users, just confusion from one person about what it meant. - Fixing static_cast char to unsigned on BIG_ENDIAN platforms. Fixes Issue 35 and Issue 36. - Comment clarification to address leveldb Issue 37. - Change license in posix_logger.h to match other files. - A build problem where uint32 was used instead of uint32_t. Sync with upstream @24408625
* Bugfixes: for Get(), don't hold mutex while writing log.gabor@google.com2011-09-011-14/+55
| | | | | | | | | | | | | | | | | | | | | | | | | | - Fix bug in Get: when it triggers a compaction, it could sometimes mark the compaction with the wrong level (if there was a gap in the set of levels examined for the Get). - Do not hold mutex while writing to the log file or to the MANIFEST file. Added a new benchmark that runs a writer thread concurrently with reader threads. Percentiles ------------------------------ micros/op: avg median 99 99.9 99.99 99.999 max ------------------------------------------------------ before: 42 38 110 225 32000 42000 48000 after: 24 20 55 65 130 1100 7000 - Fixed race in optimized Get. It should have been using the pinned memtables, not the current memtables. git-svn-id: https://leveldb.googlecode.com/svn/trunk@50 62dab493-f737-651d-591e-8d6aee1b9529
* Bugfix for issue 33; reduce lock contention in Get(), parallel benchmarks.gabor@google.com2011-08-221-13/+23
| | | | | | | | | | | | | | | | | | | | - Fix for issue 33 (non-null-terminated result from leveldb_property_value()) - Support for running multiple instances of a benchmark in parallel. - Reduce lock contention on Get(): (1) Do not hold the lock while searching memtables. (2) Shard block and table caches 16-ways. Benchmark for evaluating this change: $ db_bench --benchmarks=fillseq1,readrandom --threads=$n (fillseq1 is a small hack to make sure fillseq runs once regardless of number of threads specified on the command line). git-svn-id: https://leveldb.googlecode.com/svn/trunk@49 62dab493-f737-651d-591e-8d6aee1b9529
* @23023120dgrogan@chromium.org2011-08-061-1/+1
| | | | git-svn-id: https://leveldb.googlecode.com/svn/trunk@47 62dab493-f737-651d-591e-8d6aee1b9529
* Speed up Snappy uncompression, new Logger interface.gabor@google.com2011-07-211-28/+17
| | | | | | | | | | | | | | | | | | | | - Removed one copy of an uncompressed block contents changing the signature of Snappy_Uncompress() so it uncompresses into a flat array instead of a std::string. Speeds up readrandom ~10%. - Instead of a combination of Env/WritableFile, we now have a Logger interface that can be easily overridden applications that want to supply their own logging. - Separated out the gcc and Sun Studio parts of atomic_pointer.h so we can use 'asm', 'volatile' keywords for Sun Studio. git-svn-id: https://leveldb.googlecode.com/svn/trunk@39 62dab493-f737-651d-591e-8d6aee1b9529
* Small tweaks and bugfixes for Issue 18 and 19.gabor@google.com2011-07-151-7/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Slight tweak to the no-overlap optimization: only push to level 2 to reduce the amount of wasted space when the same small key range is being repeatedly overwritten. Fix for Issue 18: Avoid failure on Windows by avoiding deletion of lock file until the end of DestroyDB(). Fix for Issue 19: Disregard sequence numbers when checking for overlap in sstable ranges. This fixes issue 19: when writing the same key over and over again, we would generate a sequence of sstables that were never merged together since their sequence numbers were disjoint. Don't ignore map/unmap error checks. Miscellaneous fixes for small problems Sanjay found while diagnosing issue/9 and issue/16 (corruption_testr failures). - log::Reader reports the record type when it finds an unexpected type. - log::Reader no longer reports an error when it encounters an expected zero record regardless of the setting of the "checksum" flag. - Added a missing forward declaration. - Documented a side-effects of larger write buffer sizes (longer recovery time). git-svn-id: https://leveldb.googlecode.com/svn/trunk@37 62dab493-f737-651d-591e-8d6aee1b9529
* A number of smaller fixes and performance improvements:gabor@google.com2011-06-221-36/+99
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Implemented Get() directly instead of building on top of a full merging iterator stack. This speeds up the "readrandom" benchmark by up to 15-30%. - Fixed an opensource compilation problem. Added --db=<name> flag to control where the database is placed. - Automatically compact a file when we have done enough overlapping seeks to that file. - Fixed a performance bug where we would read from at least one file in a level even if none of the files overlapped the key being read. - Makefile fix for Mac OSX installations that have XCode 4 without XCode 3. - Unified the two occurrences of binary search in a file-list into one routine. - Found and fixed a bug where we would unnecessarily search the last file when looking for a key larger than all data in the level. - A fix to avoid the need for trivial move compactions and therefore gets rid of two out of five syncs in "fillseq". - Removed the MANIFEST file write when switching to a new memtable/log-file for a 10-20% improvement on fill speed on ext4. - Adding a SNAPPY setting in the Makefile for folks who have Snappy installed. Snappy compresses values and speeds up writes. git-svn-id: https://leveldb.googlecode.com/svn/trunk@32 62dab493-f737-651d-591e-8d6aee1b9529