There isn't a limit per se (that I know of), but our implementation of Memcache has two LRU (least recently used) queues that are used to expire content based on recency of access: a global LRU for that particular Memcache instance, and an LRU for your app. The amount of memory used is subject to change and I don't know it off the top of my head. I suspect you will not be able to store a billion keys, however, as I am pretty sure this'll go over the per app memory limits.
So the bigger question here is this: are you familiar with the concept of a "working set" in computer science? Chances are good you will not need all billion keys equally. Why not store all these objects in the datastore and only store the most accessed in Memcache? The easiest implementation will be to check memcache first before checking the datastore, and Memcache's LRU expiration will just take care of the rest for you. -- Ikai Lan Developer Programs Engineer, Google App Engine plus.ikailan.com On Mon, Feb 13, 2012 at 4:18 AM, Luke <travalle...@gmail.com> wrote: > Is there any limit of maximum keys i can store in memcache in any > particular time. Can store billions of keys as long as each key not > exist hardlimit 1 mb? Is there any exacts number? > > -- > You received this message because you are subscribed to the Google Groups > "Google App Engine for Java" group. > To post to this group, send email to > google-appengine-java@googlegroups.com. > To unsubscribe from this group, send email to > google-appengine-java+unsubscr...@googlegroups.com. > For more options, visit this group at > http://groups.google.com/group/google-appengine-java?hl=en. > > -- You received this message because you are subscribed to the Google Groups "Google App Engine for Java" group. To post to this group, send email to google-appengine-java@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
