Unable to install RounCube [Solved]

Hi, I’ve fresh install of yunohost (I really enjoy) all nearly perfect but…
I’ve few problems I think I will make on thread by problem…
RoundCube refuse to install

    Exécution du script « /var/cache/yunohost/from_file/roundcube_ynh-f5eb4d27a14e403080306de2334cfa20784dc48f/scripts/remove »...
Unable to update Roundcube core dependencies
+ exit 1
+ echo 'Unable to update Roundcube core dependencies'
+ ynh_die 'Unable to update Roundcube core dependencies'
install [--prefer-source] [--prefer-dist] [--dry-run] [--dev] [--no-dev] [--no-custom-installers] [--no-autoloader] [--no-scripts] [--no-progress] [--no-suggest] [-v|vv|vvv|--verbose] [-o|--optimize-autoloader] [-a|--classmap-authoritative] [--ignore-platform-reqs] [--] []...
Warning: proc_open(): fork failed - Cannot allocate memory in phar:///tmp/[yVc]K/composer.phar/vendor/symfony/console/Application.php on line 957
proc_open(): fork failed - Cannot allocate memory
[ErrorException]
PHP Warning: proc_open(): fork failed - Cannot allocate memory in phar:///tmp/[yVc]K/composer.phar/vendor/symfony/console/Application.php on line 957
Check https://getcomposer.org/doc/articles/troubleshooting.md#proc-open-fork-failed-errors for details
The following exception is caused by a lack of memory or swap, or not having swap configured
++ php '/tmp/[yVc]K/composer.phar' install --no-dev -d '/tmp/[yVc]K' --quiet --no-interaction

I try with and without carddav plugin

Have you tried the resolution method provided in the log message? (https://getcomposer.org/doc/articles/troubleshooting.md#proc-open-fork-failed-errors)

It seems like you don’t have enough memory or swap on your machine.

Ok, the link says that I have to create swap memory on my machine…
After verification with my admin its not so good to add swap on a VM so he “pushed” my memory from 512 to 2G
RoundCube installed…

Youhou
Thanks…