Controls the block size used by the LZMA2 compressor, in kilobytes, when LZMANumBlockThreads is set to 2 or higher.

Note that setting this too high can negate the benefits of using multiple block threads. Typically, the block size should be no more than the total size of your data divided by the number of block threads.

See also: LZMADictionarySize
LZMANumBlockThreads