https://bugs.documentfoundation.org/show_bug.cgi?id=158732
Bug ID: 158732
Summary: deb packages don't use the maximum force for xz
compression
Product: LibreOffice
Version: 24.8.0.0 alpha0+ Master
Hardware: All
OS: Linux (All)
Status: UNCONFIRMED
Severity: normal
Priority: medium
Component: Installation
Assignee: [email protected]
Reporter: [email protected]
>From the daily build language pack
LibreOfficeDev_24.8.0.0.alpha0_Linux_x86-64_deb_langpack_de.tar.gz, 7z tells
that the below deb package uses the xz compression method :
------------------------------
$ 7z l libreofficedev24.8-dict-de_24.8.0.0.alpha0-1_amd64.deb
[...]
Type = xz
Physical Size = 7713188
Method = LZMA2:23 CRC64
Streams = 1
Blocks = 4
------------------------------
Next, I extracted the content of this deb package with the below command :
7z x libreofficedev24.8-dict-de_24.8.0.0.alpha0-1_amd64.deb
This extracts the below file :
data.tar
Next I compressed this tar archive with xz using several compression forces :
------------------------------
$ xz -1 --threads=1 --stdout data.tar > d-1.xz
$ xz -4 --threads=1 --stdout data.tar > d-4.xz
$ xz -5 --threads=1 --stdout data.tar > d-5.xz
$ xz -9 --threads=1 --stdout data.tar > d-9.xz
------------------------------
Looking at the size of the files, it seems the deb archive doesn't use the
maximum compression force of xz :
------------------------------
$ ls -lhS *
-rw-r--r-- 1 j j 82M déc. 16 03:40 data.tar
-rw-r--r-- 1 j j 16M déc. 16 14:21 d-1.xz
-rw-r--r-- 1 j j 11M déc. 16 14:22 d-4.xz
-rw-r--r-- 1 j j 7,4M déc. 16 03:40
libreofficedev24.8-dict-de_24.8.0.0.alpha0-1_amd64.deb
-rw-r--r-- 1 j j 6,7M déc. 16 14:24 d-5.xz
-rw-r--r-- 1 j j 3,8M déc. 16 14:25 d-9.xz
------------------------------
The memory requirement on GNU/Linux in order to use LibreOffice is at least
256MB but prefered 512MB :
https://www.libreoffice.org/get-help/system-requirements/#Linux
The man page of xz tells :
"decompressing a file created with xz -9 currently requires 65 MiB of memory".
So there is no limitation to use the maximum force ("-9") for xz compression
for a LibreOffice deb package.
Users would then be able to download the deb files faster and save storage. The
servers would save storage and bandwidth. As this is a single compression for
many downloads, the maximum compression force for xz would provide an overall
benefit.
--
You are receiving this mail because:
You are the assignee for the bug.
