Class CompressingStoredFieldsFormat

A StoredFieldsFormat that is very similar to Lucene40StoredFieldsFormat but compresses documents in chunks in order to improve the compression ratio.

For a chunk size of chunkSize bytes, this StoredFieldsFormat does not support documents larger than (231 - chunkSize) bytes. In case this is a problem, you should use another format, such as Lucene40StoredFieldsFormat.

For optimal performance, you should use a MergePolicy that returns segments that have the biggest byte size first.

@lucene.experimental

Inheritance
System.Object
StoredFieldsFormat
CompressingStoredFieldsFormat
Lucene41StoredFieldsFormat
Assembly: DistributedLucene.Net.dll
Syntax
public class CompressingStoredFieldsFormat : StoredFieldsFormat

Constructors

Name Description
CompressingStoredFieldsFormat(String, CompressionMode, Int32)

Create a new CompressingStoredFieldsFormat with an empty segment suffix.
CompressingStoredFieldsFormat(String, String, CompressionMode, Int32)

Create a new CompressingStoredFieldsFormat.

formatName is the name of the format. This name will be used in the file formats to perform codec header checks (CheckHeader(DataInput, String, Int32, Int32)).

segmentSuffix is the segment suffix. this suffix is added to the result file name only if it's not the empty string.

The compressionMode parameter allows you to choose between compression algorithms that have various compression and decompression speeds so that you can pick the one that best fits your indexing and searching throughput. You should never instantiate two CompressingStoredFieldsFormats that have the same name but different Lucene.Net.Codecs.Compressing.CompressingStoredFieldsFormat.compressionModes.

chunkSize is the minimum byte size of a chunk of documents. A value of 1 can make sense if there is redundancy across fields. In that case, both performance and compression ratio should be better than with Lucene40StoredFieldsFormat with compressed fields.

Higher values of chunkSize should improve the compression ratio but will require more memory at indexing time and might make document loading a little slower (depending on the size of your OS cache compared to the size of your index).

Methods

Name Description
FieldsReader(Directory, SegmentInfo, FieldInfos, IOContext)
FieldsWriter(Directory, SegmentInfo, IOContext)
ToString()

Extension Methods