Why doesn't eAccelerator cache to harddrive?

When looking at the set folder in php.ini for eAccelerator to use, nothing is there. No hidden files as well. Directory is writable as well:

eaccelerator.cache_dir = "c:/wamp/tmp/eaccelerator"'

Also got the following settings in php.ini to allow disc cache:

eaccelerator.disk_开发者_如何学JAVAsize="12"
eaccelerator.keys="disk_only"
eaccelerator.sessions="disk_only"
eaccelerator.content="disk_only"

When checking out php_info(); following appears:

Memory Size          33,554,392 Bytes
Memory Available    29,181,672 Bytes
Memory Allocated    4,372,720 Bytes 

The allocated RAM goes up as the numbers of file's being read increases, so it's definitely caching, but why doesn't it write anything to the temp directory?

Thanks!

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Did you have the option eaccelerator.shm_only = 1? They may over-ride disk cache.

See this https://serverfault.com/questions/61316/eaccelerator-disk-cache-size