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diff --git a/SOURCES/parallel_xz.sh b/SOURCES/parallel_xz.sh
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+#!/bin/sh
+# Reads filenames on stdin, xz-compresses each in place.
+# Not optimal for "compress relatively few, large files" scenario!
+
+# How many xz's to run in parallel:
+procgroup=""
+while test "$#" != 0; do
+ # Get it from -jNUM
+ N="${1#-j}"
+ if test "$N" = "$1"; then
+ # Not -j<something> - warn and ignore
+ echo "parallel_xz: warning: unrecognized argument: '$1'"
+ else
+ procgroup="$N"
+ fi
+ shift
+done
+
+# If told to use only one cpu:
+test "$procgroup" || exec xargs -r xz
+test "$procgroup" = 1 && exec xargs -r xz
+
+# xz has some startup cost. If files are really small,
+# this cost might be significant. To combat this,
+# process several files (in sequence) by each xz process via -n 16:
+exec xargs -r -n 16 -P $procgroup xz