4. Intel(R) QuickAssist (QAT) Compression Poll Mode Driver

The QAT compression PMD provides poll mode compression & decompression driver support for the following hardware accelerator devices:

  • Intel QuickAssist Technology C62x
  • Intel QuickAssist Technology C3xxx
  • Intel QuickAssist Technology DH895x

4.1. Features

QAT compression PMD has support for:

Compression/Decompression algorithm:

  • DEFLATE - using Fixed and Dynamic Huffman encoding

Window size support:

  • 32K

Checksum generation:

  • CRC32, Adler and combined checksum

4.2. Limitations

  • Compressdev level 0, no compression, is not supported.
  • Queue pairs are not thread-safe (that is, within a single queue pair, RX and TX from different lcores is not supported).
  • No BSD support as BSD QAT kernel driver not available.
  • Number of segments in mbuf chains in the op must be <= RTE_PMD_QAT_COMP_SGL_MAX_SEGMENTS from the config file.
  • When using Deflate dynamic huffman encoding for compression, the input size (op.src.length) must be < CONFIG_RTE_PMD_QAT_COMP_IM_BUFFER_SIZE from the config file, see Build Configuration for more details.

4.3. Installation

The QAT compression PMD is built by default with a standard DPDK build.

It depends on a QAT kernel driver, see Building PMDs on QAT.