Seu limite de memória no PHP é muito baixo. Veja como você pode aumentá-lo.
The standard PHP memory requirements for Drupal core are a bare minimum. Sites that run many contrib modules, or particularly memory-intensive ones, will need more.
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php.ini
This is the recommended approach if you have access to the server's php.ini. This will not be possible in some shared hosting environments, though your host may be able to adjust it for you. Note that this change will affect all websites and PHP scripts on the server.
Locate the php.ini file used by your web server. You can click the "more information" link on Drupal's status page's PHP section. which shows the phpinfo() page. Locate the Configuration File (php.ini) Path row on that page. During installation Drupal checks the PHP Memory Limit, and if it is less than 32M (16MB for Drupal 6), an error message also provides the path to the php.ini file.
Edit the memory_limit parameter in the php.ini file (usually in a section called Resource Limits) memory_limit = 64M ; Maximum amount of memory a script may consume (64MB) If there is no section already for this, place the above line at the end of the file.
Restart Apache.