1. A method for predicting a compressibility of a block of data, comprising: extracting byte intervals from the block of data, each of the byte intervals consisting of a preselected number of bytes; performing a hash function to map the byte intervals into a plurality of bins, the plurality of bins comprising one bin for each possible value of the byte intervals; incrementing a hit count each time more than one of the byte intervals is mapped into a single bin of the plurality of bins; and determining whether to compress the block of data based on a comparison of a ratio of the hit count to a total number of the byte intervals and a preselected threshold, wherein the performing the hash function to map the byte intervals into the plurality of bins comprises performing the hash function using less than a total number of bits in the preselected number of bytes.