FYI, >From 3db1e8238af7201b991c34dd51e156b852be3304 Mon Sep 17 00:00:00 2001 From: Jim Meyering <[email protected]> Date: Sat, 3 Mar 2012 10:48:51 +0100 Subject: [PATCH 1/2] build: update gnulib submodule to latest
--- gnulib | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/gnulib b/gnulib index 9a25aef..eb21377 160000 --- a/gnulib +++ b/gnulib @@ -1 +1 @@ -Subproject commit 9a25aef6918949dd5c7f5e9209409db9aa5b145b +Subproject commit eb213779301aa663ab84ac947e8e181e9ad554d0 -- 1.7.9.2.324.g1221 >From 4b2224681fbc297bf585630b679d8540a02b78d3 Mon Sep 17 00:00:00 2001 From: Jim Meyering <[email protected]> Date: Sat, 3 Mar 2012 10:51:11 +0100 Subject: [PATCH 2/2] maint: use an optimal-for-grep xz compression setting * cfg.mk (XZ_OPT): Use -6e (determined empirically, see comments). This sacrifices a meager 60 bytes of compressed tarball size for a 55-MiB decrease in the memory required during decompression. I.e., using -9e would shave off only 60 bytes from the tar.xz file, yet would force every decompression process to use 55 MiB more memory. --- cfg.mk | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/cfg.mk b/cfg.mk index 08bb156..84115c2 100644 --- a/cfg.mk +++ b/cfg.mk @@ -31,6 +31,26 @@ bootstrap-tools = autoconf,automake,gnulib # Now that we have better tests, make this the default. export VERBOSE = yes +# Comparing tarball sizes compressed using different xz presets, we see +# that -6e adds only 60 bytes to the size of the tarball, yet reduces +# (from -9) the decompression memory requirement from 64 MiB to 9 MiB. +# Don't be tempted by -5e, since -6 and -5 use the same dictionary size. +# $ for i in {4,5,6,7,8,9}{e,}; do \ +# (n=$(xz -$i < grep-2.11.tar|wc -c);echo $n $i) & done |sort -nr +# 1236632 4 +# 1162564 5 +# 1140988 4e +# 1139620 6 +# 1139480 7 +# 1139480 8 +# 1139480 9 +# 1129552 5e +# 1127616 6e +# 1127556 7e +# 1127556 8e +# 1127556 9e +export XZ_OPT = -6e + old_NEWS_hash = 347e90ee0ec0489707df139ca3539934 # Many m4 macros names once began with `jm_'. -- 1.7.9.2.324.g1221
