On Wed, Dec 31, 2014 at 01:59:51AM +1000, Allan McRae wrote:

On 31/12/14 01:14, Mohammad Alsaleh wrote:

...

* Add -9 which is the highest compression level. * Use lzma for secondary compression.

I believe I said a patch adding '-9 -S djw' would be accepted in the last discussion of this.

How does lzma for secondary compression compare to djw in terms of memory footprint and speed?

Using an aging Laptop (Core 2 Due). Time is the samllest in 4 runs. inkscape: 05.765s 139.50MiB default 09.748s 235.02MiB -9 -S djw 09.315s 242.86MiB -9 -S lzma clang: 15.492s 140.46MiB default 36.503s 236.11MiB -9 -S djw 39.293s 243.68MiB -9 -S lzma

...

Decompression speed is largely unaffected as most cycles are consumed by xz for re-compression.

Some numbers:

clang x86_64 [3.5.0-2.1 to 3.5.0-3] 17.21MiB default (0.73) 15.67MiB -9 (0.67) 13.59MiB -9 -S djw (0.58) 12.01MiB -9 -S lzma (0.51)

inkscape x86_64 [0.48.5-3 to 0.48.5-4] 02.69MiB default (0.21) 01.64MiB -9 (0.13) 01.30MiB -9 -S djw (0.10) 01.01MiB -9 -S lzma (0.08)

Signed-off-by: Mohammad Alsaleh --- scripts/pkgdelta.sh.in | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/scripts/pkgdelta.sh.in b/scripts/pkgdelta.sh.in index be49326..fe63974 100644 --- a/scripts/pkgdelta.sh.in +++ b/scripts/pkgdelta.sh.in @@ -140,7 +140,7 @@ create_xdelta() deltafile=$(dirname "$newfile")/$pkgname-${oldver}_to_${newver}-$arch.delta local ret=0

- xdelta3 -q -f -s "$oldfile" "$newfile" "$deltafile" || ret=$? + xdelta3 -q -f -9 -S lzma -s "$oldfile" "$newfile" "$deltafile" || ret=$? if (( ret )); then error "$(gettext "Delta could not be created.")" return 1