diff --git a/contrib/pzstd/README.md b/contrib/pzstd/README.md index 1a5a0105..eba64085 100644 --- a/contrib/pzstd/README.md +++ b/contrib/pzstd/README.md @@ -1,6 +1,7 @@ # Parallel Zstandard (PZstandard) -Parallel Zstandard provides Zstandard format compatible compression and decompression that is able to utilize multiple cores. +Parallel Zstandard is a Pigz-like tool for Zstandard. +It provides Zstandard format compatible compression and decompression that is able to utilize multiple cores. It breaks the input up into equal sized chunks and compresses each chunk independently into a Zstandard frame. It then concatenates the frames together to produce the final compressed output. Optionally, with the `-p` option, PZstandard will write a 12 byte header for each frame that is a skippable frame in the Zstandard format, which tells PZstandard the size of the next compressed frame. @@ -31,11 +32,11 @@ Compression Speed vs Ratio with 4 Threads | Decompression Speed with 4 Threads The test procedure was to run each of the following commands 2 times for each compression level, and take the minimum time. - time ./pzstd -# -n 4 -p -c silesia.tar > silesia.tar.zst - time ./pzstd -d -n 4 -c silesia.tar.zst > /dev/null + time pzstd -# -n 4 -p -c silesia.tar > silesia.tar.zst + time pzstd -d -n 4 -c silesia.tar.zst > /dev/null - time pigz -# -p 4 -k -c silesia.tar > silesia.tar.gz - time pigz -d -p 4 -k -c silesia.tar.gz > /dev/null + time pigz -# -p 4 -k -c silesia.tar > silesia.tar.gz + time pigz -d -p 4 -k -c silesia.tar.gz > /dev/null PZstandard was tested using compression levels 1-19, and Pigz was tested using compression levels 1-9. Pigz cannot do parallel decompression, it simply does each of reading, decompression, and writing on separate threads.