Prefix based FileSystem Optimization

    Note: This feature works only when is enabled which means that Hadoop Compatible File System compatibility is favored instead of S3 compatibility. Some irregular S3 key names may be rejected or normalized.

    This feature is strongly recommended to be turned ON when Ozone buckets are mainly used via Hadoop compatible interfaces, especially with high number of files in deep directory hierarchy.

    Simple is the existing OM metadata format, which stores key entry with full path name. In Prefix based optimization, OM metadata format stores intermediate directories into and files into as shown in the below picture. The key to the table is the name of a directory or a file prefixed by the unique identifier of its parent directory, .

    Directory rename operation with prefix layout:

    Following picture describes the OM metadata changes while performing a rename operation on a directory. FSO Rename

    Configuration

    By default the feature is disabled. It can be enabled with the following settings in :