Intel® QAT Compress and Verify Tests

For each compress request, Intel® QAT calculates two checksums based on protocol requirements.

For the Deflate algorithm, both Adler-32 and CRC-32 are calculated. This allows the compressed dataset to be delivered as either a GZIP block (based on RFC 1952) or a zlib block (based on RFC 1950), respectively.

For the LZ4 algorithm, XXHash-32 is generated for correct LZ4 blocks and frames, and CRC-32 is also produced.

The production of LZ4 also generates XXHash-32 and CRC-32.

A complete Compress and Verify test on a deflate block can be described using C code notation as shown below:

if ((comp_opr == SUCCESS) && (decomp_opr == SUCCESS) &&
    (comp_textlen == dcomp_textlen) &&
    (comp_crc32 == decomp_crc32)) && (comp_adler32 == decomp_adler32))
{
   CnV = TRUE;
}
else
{
   CnV = FALSE;
}

A complete Compress and Verify test on an LZ4 or LZ4s block can be described as:

if ((comp_opr == SUCCESS) && (decomp_opr == SUCCESS) &&
    (comp_textlen == dcomp_textlen) &&
    (comp_crc32 == decomp_crc32 ) && (comp_xxhash32 == decomp_xxhash32))
{
   CnV = TRUE;
}
else
{
   CnV = FALSE;
}

Where:

Term	Meaning
comp_opr	compression operation
decomp_opr	decompression operation
comp_textlen	size of the incoming cleartext dataset
decomp_textlen	size of the decompressed dataset
comp_crc32	CRC32 of the incoming cleartext dataset
decomp_crc32	CRC32 of the decompressed dataset
comp_adler32	Adler32 of the incoming cleartext dataset
decomp_adler32	Adler32 of the decompressed dataset
comp_xxhash32	XXHash32 of the incoming cleartext dataset
decomp_xxhas32	XXHash32 of the decompressed dataset