From 6daa4d0ea46a8441f21f609149f3633158bf4704 Mon Sep 17 00:00:00 2001 From: Lasse Collin Date: Tue, 23 Jan 2024 18:29:28 +0200 Subject: xz: Use threaded mode by defaut (as if --threads=0 was used). This hopefully does more good than bad: + It's faster by default. + Only the threaded compressor creates files that can be decompressed in threaded mode. - Compression ratio is worse, usually not too much though. When it matters, -T1 must be used. - Memory usage increases. - Scripts that assume single-threaded mode but don't use -T1 will possibly use too much resources, for example, if they run multiple xz processes in parallel to compress multiple files. - Output from single-threaded and multi-threaded compressors differ but such changes could happen for other reasons too (they just haven't happened since 5.0.0). --- src/xz/xz.1 | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'src/xz/xz.1') diff --git a/src/xz/xz.1 b/src/xz/xz.1 index 3c09309b..950585f8 100644 --- a/src/xz/xz.1 +++ b/src/xz/xz.1 @@ -1303,6 +1303,15 @@ meet this condition, but files compressed in single-threaded mode don't even if .BI \-\-block\-size= size has been used. +.IP "" +The default value for +.I threads +is +.BR 0 . +In +.B xz +5.4.x and older the default is +.BR 1 . . .SS "Custom compressor filter chains" A custom filter chain allows specifying -- cgit v1.2.3