On 07/07/2014 02:56 PM, Reindl Harald wrote:
Am 07.07.2014 14:53, schrieb Ljubomir Ljubojevic:
Also, check needs to be made if xz supports multitrheading like pk7zip
enter "xz --help" would have answered this
--threads=NUM use at most NUM threads; the default is 1; set to 0 to use the number of processor cores
Usage: xz [OPTION]... [FILE]... Compress or decompress FILEs in the .xz format.
-z, --compress force compression -d, --decompress, --uncompress force decompression -t, --test test compressed file integrity -l, --list list information about .xz files -k, --keep keep (don't delete) input files -f, --force force overwrite of output file and (de)compress links -c, --stdout, --to-stdout write to standard output and don't delete input files -0 ... -9 compression preset; default is 6; take compressor *and* decompressor memory usage into account before using 7-9! -e, --extreme try to improve compression ratio by using more CPU time; does not affect decompressor memory requirements -T, --threads=NUM use at most NUM threads; the default is 1; set to 0 to use the number of processor cores -q, --quiet suppress warnings; specify twice to suppress errors too -v, --verbose be verbose; specify twice for even more verbose -h, --help display this short help and exit -H, --long-help display the long help (lists also the advanced options) -V, --version display the version number and exit
Ok, I spent several minutes on this.
xz --long-help and man xz are much more informative.
https://en.wikipedia.org/wiki/Xz:
"Design xz compresses single files as input, and does not bundle multiple files into a single archive. It is therefore common to compress a file that is itself an archive, such as those created by the tar or cpio Unix programs.[2]"
"xz is a lossless data compression program and file format which incorporates the LZMA compression algorithm.
xz can be thought of as a stripped down version of the 7-Zip program. xz has its own file format rather than the .7z format used by 7-Zip (which lacks support for Unix-like file system metadata[2])."
https://en.wikipedia.org/wiki/7-Zip:
"By default, 7-Zip creates 7z format archives with a .7z file extension. Each archive can contain multiple directories and files. As a container format, security or size reduction are achieved using a stacked combination of filters. These can consist of pre-processors, compression algorithms, and encryption filters."
So either tar.xz or 7z container, and looks like LZM2 is only option, with several switches for xz for block reduction.
And, no, --help does not actually help with assessing if xz is viable replacement for some particular purpose, testing is needed.
P.S. You should REALLY fix your mail client, to sent replies to centos@centos.org so that conversations is seen by others (it looks like you reply 99% to the person instead back to the list).