Apache Accumulo 1.7.2 发布 K/V 存储方案

Apache Accumulo 1.7.2 发布了，Apache Accumulo 是一个可靠的、可伸缩的、高性能的排序分布式的 Key-Value 存储解决方案，基于单元访问控制以及可定制的服务器端处理。使用 Google BigTable 设计思路，基于 hadoop”>Apache Hadoop、Zookeeper 和 thrift”>Thrift 构建。

一些提升：

Write-Ahead Logs can be prematurely deleted
Upgrading to Apache Commons VFS 2.1
Native Map failed to increment mutation count properly
Open WAL files could prevent DataNode decomission
Remove unnecessary copy of cached RFile index blocks
Analyze Key-length to avoid choosing large Keys for RFile Index blocks
Minor performance improvements.

其他改变：

ACCUMULO-3923 bootstrap_hdfs.sh script would copy incorrect jars to hdfs.
ACCUMULO-4146 Avoid copy of RFile Index Blocks when already in cache.
ACCUMULO-4155 No longer publish javadoc for non-public API to website. (Still available in javadoc jars in maven)
ACCUMULO-4173 Provide balancer to balance table within subset of hosts.
ACCUMULO-4334 Ingest rates reported through JMX did not match rates reported by Monitor.
ACCUMULO-4335 Error conditions that result in a Halt should ensure non-zero process exit code