New Instalation. mmap() failed: [12] Cannot allocate memory

I am triying to install OXID ESHOP VERSION 6.0.3 in a Ionos 1and1 Server.

Mit putty (ssh) I write:

php7.1-cli composer.phar create-project --no-dev oxid-esales/oxideshop-project oxid dev-b-6.1-ce

But I get this error:

mmap() failed: [12] Cannot allocate memory

Fatal error: Out of memory (allocated 607129600) (tried to allocate 14680096 bytes) in phar:///homepages/5/d458727760/htdocs/oxid/composer.phar/src/Composer/Util/RemoteFilesystem.php on line 594

Memory_limit is set in ‘800M’

Anybody can help me on this installation?

Thanks.

Fernando.

800m is memory limit for php when run by webserver, but when running php from cli there is probably another value.
try this:
php --info |grep memory_limit

This is what I get: -1

(uiserver):u72466909:~/oxid$ php7.1-cli --info |grep memory_limit
memory_limit => -1 => -1

in this case memory limitation comes from the OS, not from PHP itself.
Try manually setting memory limit to 800m and if it does not work, you probably need assiastance from 1and1 support.