如何在$ _SESSION中存储数据与memcache（d）不同？

Question

The obvious difference is that when stored in memcache(d) data becomes available cross the system. Sessions store data per user, though, session_id() could theoretically be used to share this data with more users.

However, in terms of performance, speed and memory usage - is there a difference?

Answer 1

PHP sessions are stored in the filesystem by default. You can modify this behaviour so that they are saved in a database, or in your case memcached.

So in terms of performance, memcached is generally faster than the filesystem. This obviously depends on your environment.

See session_set_save_handler