我正试图更新我的compose，但我得到以下错误信息，有人能告诉我这是什么吗？
root@linuxmachine:/var/www/html/# composer update
Do not run Composer as root/super user! See https://getcomposer.org/root for details
Loading composer repositories with package information
Updating dependencies (including require-dev)
mmap() failed: [12] Cannot allocate memory
mmap() failed: [12] Cannot allocate memory
PHP Fatal error: Out of memory (allocated 815800320) (tried to allocate 4096 bytes) in phar:///usr/local/bin/composer/src/Composer/DependencyResolver/Solver.php on line 223
Fatal error: Out of memory (allocated 815800320) (tried to allocate 4096 bytes) in phar:///usr/local/bin/composer/src/Composer/DependencyResolver/Solver.php on line 223
通常这是php.ini中 "memory_limit "指令的问题。试试增加memory_limit的值。