Enum FileSystemStorageImplementation

The store module allows you to control how index data is stored and accessed on disk.

public enum FileSystemStorageImplementation

Name	Description
Default	The default type is a hybrid of NIO FS and MMapFS, which chooses the best file system for each type of file. Currently only the Lucene term dictionary and doc values files are memory mapped to reduce the impact on the operating system. All other files are opened using Lucene NIOFSDirectory.
MMap	The MMap FS type stores the shard index on the file system (maps to Lucene MMapDirectory) by mapping a file into memory (mmap). Memory mapping uses up a portion of the virtual memory address space in your process equal to the size of the file being mapped. Before using this class, be sure you have allowed plenty of virtual address space.
NIO	The NIO FS type stores the shard index on the file system (maps to Lucene NIOFSDirectory) using NIO. It allows multiple threads to read from the same file concurrently. It is not recommended on Windows because of a bug in the SUN Java implementation.
Simple	The Simple FS type is a straightforward implementation of file system storage (maps to Lucene SimpleFsDirectory) using a random access file. This implementation has poor concurrent performance (multiple threads will bottleneck). It is usually better to use the niofs when you need index persistence.