HDFS-3107 - Support for file truncate
系统支持在事务终止时undo底层存储。之前,HDFS不支持truncate(Posix标准操作),这使得上层应用采用丑陋的措施来克服这种限制。
HDFS-7584 - Support for quotas per storage type
存储类型配额:如在目标目录下对不同存储类型(SSD,DISK,ARCHIVE)空间使用的硬限制。为命令{{hdfs dfsadmin -setSpaceQuota/-clrSpaceQuota}}增加了API {{SetQuotaByStorageType}}和选项{{-storagetype}},用以set/clear目标目录下的存储类型配额。
HDFS-3689 - Support for files with variable-length blocks
HDFS现在可以选择附加数据到新block而不是最后那部分的block。用户可以通过{{CreateFlag.APPEND}}和{{CreateFlag.NEW_BLOCK}}到{{append}}API来实现这个要求。HDFS现在允许用户通过{{SyncFlag.END_BLOCK}}到{{hsync}}API来结束当前block并将剩余数据写入新块。
HDFS-5040 - You can now see an audit log for admin commands and output the log of all DFS admin commands.
HDFS-10240 - Fixed an issue where the race between close/recoverLease leads to missing blocks.
HDFS-10453 - Fixed an issue where the ReplicationMonitor thread could get stuck for a long time due to the race between replication and delete of the same file in a large cluster.
HDFS-13051 - Fixed an issue where a deadlock occurs when rolleditlog rpc call happens and editPendingQ is full.
HDFS-13178 - Add a force option to DiskBalancer Execute command
HDFS-13181 - Add a configuration to DiskBalancer for valid plan hours
HDFS-13281 - Fixed an issue where the Namenode#createFile was not /.reserved/raw/ aware.
HDFS-13314 - NameNode optionally exits if it detects FsImage corruption
HDFS-13322 - FUSE lib now recognizes the change of the Kerberos ticket cache path if it was changed with the KRB5CCNAME environment variable during the same user session.
HDFS-13339 - Fixed an issue where volume reference cannot be released and may lead to deadlock when DataXceiver does a check volume
HDFS-13721 - Fixed an NPE in DataNode due to an uninitialized DiskBalancer.
HDFS-13727 - The DiskBalancer now logs a full stack trace if it exits with an unhandled exception.
HDFS-13813 - Added a check to see if a child inode exists in the global FSDirectory dir when saving (serializing) INodeDirectorySection.
不支持的特性
HDFS
ACLs for the NFS gateway
Aliyun Cloud Connector
Erasure Coding
HDFS NameNode Federation
HDFS Router Based Federation
HDFS truncate
More than two NameNodes
Openstack Swift
Quota support for Storage Types
SFTP FileSystem
Upgrade Domain
Variable length block
ZStandard Compression Codec
HDFS NFS网关只在RHEL-compatible系统work as shipped(“out of the box”)。由于portmap/rpcbind在本地版本的一个bug,在SLES或Ubuntu系统HDFS NFS网关不会work as shipped。支持RHEL-compatible版本在rpcbind-0.2.0-10.el6及以上,或使用CM安装CDH,或使用ROOT启动网关。 措施和注意事项:
在RHEL-compatible系统,确保版本大于等于rpcbind-0.2.0-10.el6。
在SLES或Ubuntu系统:
o 用CM安装CDH; or
o 用ROOT启动网关; or
o 不用PKG启动网关; or
o 在insecure模式运行rpcbind 启动网关,使用-i 选项,但这将允许任何人从远程主机绑定到端口映射。 Upstream Issue: 731542 (Red Hat), 823364 (SLES)