busybox/archival
Daniel Edgecumbe c660cc1b77 gzip: set default compression level to 6 when CONFIG_FEATURE_GZIP_LEVELS=n
With this change, GNU gzip -n and BusyBox gzip now produce identical output
assuming that CONFIG_GZIP_FAST=2.

>> Excuse me, but I wonder one thing: Why should we follow
>> strictly with gzip on the no-options default behavior?

> First, the default 6 compression level is a de-facto standard. BSD gzip
> and Apple gzip (on macOS) use this default as well. So there is a
> reasonable expectation that different gzip implementations act the same.
> For instance, if the default for busybox gzip becomes 9, then someone
> writing a script using busybox gzip could reasonably expect that the
> compression level will still be 9 when the same script is run on another
> system. That would be wrong. Implementations should not deviate from
> de-facto standards without a strong reason.
>
> Second, the inherent reason for this default has not gone away. While
> processor speeds have exploded since the default was set, so has the
> typical size of compressed files. Multiple gigabytes are nothing unusual
> these days. And gzip is often used for compression on the fly, precisely
> because it offers a good compromise between speed and compression ratio.
> So I believe 6 continues to be a reasonable default.

function                                             old     new   delta
deflate                                              939     927     -12

Signed-off-by: Daniel Edgecumbe <git@esotericnonsense.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2019-09-05 13:26:58 +02:00
..
libarchive libbb: reduce the overhead of single parameter bb_error_msg() calls 2019-07-02 11:35:03 +02:00
ar.c regularize format of source file headers, no code changes 2017-09-18 16:28:43 +02:00
bbunzip_test2.sh
bbunzip_test3.sh
bbunzip_test.sh
bbunzip.c libbb: reduce the overhead of single parameter bb_error_msg() calls 2019-07-02 11:35:03 +02:00
bzip2.c libbb: reduce the overhead of single parameter bb_error_msg() calls 2019-07-02 11:35:03 +02:00
Config.src restore documentation on the build config language 2018-06-06 15:16:48 +02:00
cpio.c config: update size information 2018-12-28 03:20:17 +01:00
dpkg_deb.c config: dpkg_deb should be dpkg-deb 2018-12-28 18:24:45 +01:00
dpkg.c libbb: reduce the overhead of single parameter bb_error_msg() calls 2019-07-02 11:35:03 +02:00
gzip.c gzip: set default compression level to 6 when CONFIG_FEATURE_GZIP_LEVELS=n 2019-09-05 13:26:58 +02:00
Kbuild.src cpio: implement -R/--owner 2015-10-16 17:24:46 +02:00
lzop.c libbb: reduce the overhead of single parameter bb_error_msg() calls 2019-07-02 11:35:03 +02:00
rpm.c libbb: reduce the overhead of single parameter bb_error_msg() calls 2019-07-02 11:35:03 +02:00
rpm.h *: make GNU licensing statement forms more regular 2010-08-16 20:14:46 +02:00
tar_symlink_attack tar: postpone creation of symlinks with "suspicious" targets. Closes 8411 2017-07-24 17:20:13 +02:00
tar.c tar: change -a from meaning "lzma" to mean "autodetect by extension" 2019-08-02 15:19:56 +02:00
unzip.c libbb: reduce the overhead of single parameter bb_error_msg() calls 2019-07-02 11:35:03 +02:00