(PECL memcached >= 2.0.0)
Memcached::getAllKeys — Gets the keys stored on all the servers
Memcached::getAllKeys() queries each memcache server and retrieves an array of all keys stored on them at that point in time. This is not an atomic operation, so it isn't a truly consistent snapshot of the keys at point in time. As memcache doesn't guarantee to return all keys you also cannot assume that all keys have been returned.
This function has no parameters.
Returns the keys stored on all the servers on success or FALSE on failure.
First I use the lastest memcached version 1.4.25, but unfortunately I found memcached::getAllkeys do not work with it, though i follow the others suggestion to disable Memcached::OPT_BINARY_PROTOCOL. So i try to use history versions, when i use memcached version 1.4.17, it works.
I got this answer..
My libmemcached version is 1.0.18. php-memcached version is 2.2.0
In Libmemcached at memcache.h line 84:
#define MAX_NUMBER_OF_SLAB_CLASSES (63 + 1)
Modify it to 201, compile again. It's ok.
主要还是版本不兼容造成的。libmemchaed里的一个bug，
memcached_return_t这个方法里的for循环，最大数是200，和上面的常量64定义不一致造成的。
This command returns always FALSE when binary protocol in use (Memcached::OPT_BINARY_PROTOCOL = true). Without binary protocol it works.
