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I am running Drupal 7.23 and drush 5.9
I can clear all caches in Drupal without an error but get "memory exhausted" if I try using drush cc all. I get "memory exhausted" when using "drush up", after it has downloaded and updated modules but was able to download and update the modules from within Drupal.
Is there anything that might be leading to a greater need for memory when using drush?