发布于 2015-07-15 07:52:22 | 268 次阅读 | 评论: 0 | 来源: 网友投递

这里有新鲜出炉的精品教程，程序狗速度看过来！

RocksDB key-value存储系统

RocksDB 是一个来自 facebook 的可嵌入式的支持持久化的 key-value 存储系统，也可作为 C/S 模式下的存储数据库，但主要目的还是嵌入式。RocksDB 基于 LevelDB 构建。

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此版本更新内容如下：

新特性

• Added experimental support for optimistic transactions.

• Added a new way to report QPS from db_bench (check out --report_file and --report_interval_seconds)

• Added a cache for individual rows. See DBOptions::row_cache for more info.

• Several new features on EventListener (see include/rocksdb/listener.h):

  • OnCompationCompleted() now returns per-compaciton job statistics, defined in include/rocksdb/compaction_job_stats.h.

  • Added OnTableFileCreated() and OnTableFileDeleted().

• Add compaction_options_universal.enable_trivial_move to true

公共 API 改进

• EventListener::OnFlushCompleted() now passes FlushJobInfo instead of a list of parameters.

• DB::GetDbIdentity() is now a const function.  If this function is overridden in your application, be sure to also make GetDbIdentity() const to avoid compile error.

• Move listeners from ColumnFamilyOptions to DBOptions.

• Add max_write_buffer_number_to_maintain option

• DB::CompactRange()'s parameter reduce_level is changed to change_level, to allow users to move levels to lower levels if allowed. It can be used to migrate a DB from options.level_compaction_dynamic_level_bytes=false to options.level_compaction_dynamic_level_bytes.true.

• Change default value for options.compaction_filter_factory and options.compaction_filter_factory_v2 to nullptr instead of DefaultCompactionFilterFactory and DefaultCompactionFilterFactoryV2.

• If CancelAllBackgroundWork is called without doing a flush after doing loads with WAL disabled, the changes which haven't been flushed before the call to CancelAllBackgroundWork will be lost.

• WBWIIterator::Entry() now returns WriteEntry instead of const WriteEntry&

• options.hard_rate_limit is deprecated.

• When options.soft_rate_limit or options.level0_slowdown_writes_trigger is triggered, the way to slow down writes is changed to: write rate to DB is limited to to options.delayed_write_rate.

• DB::GetApproximateSizes() adds a parameter to allow the estimation to include data in mem table, with default to be not to include.

• DB::CompactRange() now accept CompactRangeOptions instead of multiple paramters.

• CompactRange() will now skip bottommost level compaction for level based compaction if there is no compaction filter, bottommost_level_compaction is introduced in CompactRangeOptions to control when it's possbile to skip bottommost level compaction.

• Add Cache.GetPinnedUsage() to get the size of memory occupied by entries that are in use by the system.

• DB:Open() will fail if the compression specified in Options is not linked with the binary.

• We changed how we account for memory used in block cache.

• Add BackupEngineImpl.options_.max_background_operations to specify the maximum number of operations that may be performed in parallel.

下载：https://github.com/facebook/rocksdb/archive/v3.12.zip。

RocksDB 是一个来自 facebook 的可嵌入式的支持持久化的 key-value 存储系统，也可作为 C/S 模式下的存储数据库，但主要目的还是嵌入式。RocksDB 基于 LevelDB 构建。

历史版本 :
RocksDB 5.9.2 发布，可持久化 key-value 存储系统
RocksDB 5.8.8 发布，可持久化 key-value 存储系统
RocksDB 5.8.7 和 5.7.5 发布，key-value 存储系统
RocksDB 5.8.6 发布，可持久化 key-value 存储系统
RocksDB 5.8 发布，可持久化 key-value 存储系统
RocksDB 5.7.3 发布，可持久化 key-value 存储系统
RocksDB 5.7.2 发布，可持久化 key-value 存储系统
RocksDB 5.7.1 发布，可持久化 key-value 存储系统
RocksDB 5.6.1 发布，可持久化 key-value 存储系统
RocksDB 5.5.4 和 5.5.5 发布，修改开源授权协议
RocksDB 5.5.2 发布，可持久化 key-value 存储系统
RocksDB 5.5.1 和 5.4.7 发布，可持久化 key-value 存储系统