Recently, i had to update my virtual private server at hosteurope (one of the big hosting players in germany) and got a machine with ubuntu release 10.04 and plesk 10.4.4 installed.
Problem
Imagemagick was very slow – converting even small images needed alot processing power and a lot of time. This wasn’t acceptable since this high load was rendering my server useless after uploading a new image or clearing the thumbnail cache on my YAPB-Installation. This wasn’t the imagemagick behaviour i was used to expierience:
# time convert -resize 100x100 source.jpg target.jpg
real 0m7.693s
user 0m7.615s
sys 0m0.024s
Analysis
After searching for the phenomen for quite a time i stumbled over this article – It seems that some library is buggy thus thwarting out all image conversion processes on my machine.
Solution
As proposed, i’d tried to recompile imagemagick with the option –disable-openmp. Sadly, this wasn’t exactly an easy job since the imagemagick resisted to work properly afterwards quitting resize-jobs with the error message “no code delegate for this image“. I’m not such a linux-talker after all: fine.
Since i needed some time to figure it out – here a little step-4-step tutorial to install all needed delegates and to compile imagemagick. The actual directories may have to be adapted since i installed this at 11-2011 downloading ImageMagick 6.7.3-7. Please note that you may also need to prefix most of the bash-commands with the command “sudo” if you’re not logged in as root (which is probably the more secure way to do things on a linux bash).
Update sources.list
First, i needed to update my sources.list so i could install the needed delegates via apt-get:
# vi /etc/apt/sources.list
There i inserted a new line for my distribution
deb-src http://de.archive.ubuntu.com/ubuntu lucid main restricted universe multiverse
If you’re searching for the entry needed for your own distribution, have a look on this page:
http://wiki.ubuntuusers.de/sources.list (german page)
Install all needed infrastructure
After that i startet an update and installed all needed components for an imagemagick-compilation this way:
# apt-get update
# apt-get install build-essential
# apt-get build-dep imagemagick
The third step also neatly installed all needed delegates for my everyday work like libjpeg and libpng for the according support.
Download and compile ImageMagick
After installing the needed infrastructure i went to my root user folder, downloaded Imagemagick, configured and compiled it.
# cd ~
# wget ftp://ftp.imagemagick.org/pub/ImageMagick/ImageMagick.tar.gz
# tar xvfz ImageMagick.tar.gz
# cd ImageMagick-6.7.3-7
# ./configure '--prefix=/usr' '--mandir=${prefix}/share/man' '--infodir=${prefix}/share/info' '--with-gs-font-dir=/usr/share/fonts/type1/gsfonts' '--with-magick-plus-plus' '--with-djvu' '--enable-shared' '--without-dps' '--without-fpx' '--with-perl-options=INSTALLDIRS=vendor' 'CFLAGS=-g -O2' 'LDFLAGS=-Wl,-Bsymbolic-functions' 'CPPFLAGS=' 'CXXFLAGS=-g -O2' '--disable-openmp'
# make install
I did get the options for ./configure from the lame version already being installed on my system:
# /usr/bin/convert -list configure
The only thing i did was to remove all X11-Options (my VPS is a headless system without GUI) and adding the initially recommended –disable-openmp option.
Replace the old version
After that, i had a newly compilated version of ImageMagick lying under ~/ImageMagick-6.7.3-7/utilities – Last step was to backup the existing version of convert and to copy the new version to /usr/local/bin:
# cd /usr/local/bin
There already was a convert – i renamed it:
# mv ./convert ./convert-old-6.5.7-8
Now i copied the new version into the location
# cp ~/ImageMagick-6.7.3-7/utilities/convert .
Enjoy the beauty of fast image resizing
Voila – Now, convert was running again in acceptable speed:
# time convert -resize 100x100 source.jpg target.jpg
real 0m0.039s
user 0m0.023s
sys 0m0.016s
erreichen.